Computer Literacy Workbook

1996-1997 Printing, 3rd Edition

William T. Verts

Solutions to Sample Midterm Exam

Pages 390-402

While many of the questions are complete in this document, you will find it useful to have your workbook available for the diagrams and pictures that they refer to.

Visitors since March 15, 1997

Index

Jump to Part 1 -- General Questions
Jump to Part 2 -- MS-DOS Review
Jump to Part 3 -- Microsoft Windows
Jump to Part 4 -- Word Processing & Window Write
Jump to Part 5 -- Spreadsheets & Lotus 1-2-3

PART 1 -- General Questions

#1 -- True or False

A. A 3.5 inch diskette is a "hard disk"
FALSE. Even though it has a hard shell, the disk inside is still "floppy". A hard disk is generally a permanently mounted internal disk that can store considerably more information than can a floppy.
B. Steve Jobs was the founder of IBM Corporation
FALSE. After his success with the 1890 census tabulator, Herman Hollerith formed a company that eventually became what we know as IBM. Steve Jobs, along with Steve Wozniak, formed Apple Corporation in the late 1970's.
C. Jacquard's loom and Hollerith's tabulator both used paper tape.
FALSE. Paper tape is a continuous belt of paper, with rows of holes across the paper to contain information. The loom and the tabulator both used punched cards, where the cards were discrete rather than continuous (replacing one card is simpler than replacing an entire tape because of a small error).
D. Jacquard's 1801 loom used magnetic tape to control its weaving patterns.
FALSE. Magnetic tape dates from the 1940's and 1950's. As described above, the loom used punched cards. Examples of working Jacquard looms are in the Shelburne Museum in Shelburne, Vermont (just south of Burlington) and in the Deutsches Museum in Munich, Germany.
E. A slide rule is a digital calculating device (rather than analog)
FALSE. Because the sliding stick has an infinite number of allowable positions, including between the etched markings, the device is analog. With such a device you can get an accurate answer quickly, but not a very precise answer because of the physical limits to the number of marks that can be etched into the sticks.
F. The odometer in a car is really an analog recording device
TRUE. On most cars, the odometer measures the distance travelled by translating the rotation of the tires into rotation of the recording wheels (the digits on the odometer). The fact that the odometer wheels can be between successive digits (i.e., between .4 and .5 miles) is a clear indication that this is an analog device. I don't know for certain, but I suspect that for fancy cars with digital displays most of that system is still analog, and the information is converted to digital form at the last minute.
G. Getting a file from a hard disk takes the same time as from a floppy disk.
FALSE. Because hard disks are machined to tighter tolerances and (generally) are not designed to be removed and carried around, they have much higher information density and can spin at much faster rates than floppy disks. This means that data goes to and comes from hard disks at much higher speeds than to and from floppies.
H. Floppy disks can be used for archiving information

TRUE. Copy your sensitive files to floppies and store them away in a safe place. Since floppies don't hold very much information (1.44 Megabytes, typically), you may find that saving large files or a lot of files will require a lot of floppies, or some alternative method such as a ZIP drive from IOmega (100 megabytes per disk), a tape drive, or one of the newer removable hard drives.
I. RAM loses its contents when you turn the power off to the computer

TRUE. Current technology is such that most RAM chips require a continuous flow of power to keep their contents alive. A short number of year from now, this may no longer be true (although I've been saying this for several years already).
There is a technology called Flash RAM which is non-volatile (retains its data after power off), but it is expensive, has a limited number of times that it can be stored to, and does not come in as big a size as normal RAM. Flash RAM is often used in computers for holding portions of the operating system (the BIOS) or in modems for holding their operating software. In both cases the stored material is updated infrequently if at all. Also, digital cameras use Flash RAM instead of film for holding the captured images.
J. The contents of ROM can't be modified by ordinary computer users

TRUE. ROM, or Read Only Memory, can only be set up (or "burned") by special equipment, not generally available to normal consumers. Since ROM cannot be changed by users, nor does it lose its contents on power off, it is used to hold vital information that must be present for a computer to run (such as the Power On Self Test routines, the BIOS code for interfacing programs to the hardware, and the bootstrap loader). A hand-held dictionary or language translator has all of its words stored in ROM, which we as users don't need to change.
K. In many programs the DEL key deletes characters to the left of the cursor
FALSE. Usually the Back Space key deletes to the left of the cursor, and the DEL deletes to the right (or deletes a highlighted block of text).
L. A parity bit is an extra bit put on a byte, used to detect transmission errors

TRUE. Sending characters one bit at a time over a noisy telephone line means that occasionally a 1 gets changed to a 0 or a 0 to a 1. By sending an extra bit you can detect if one of the data bits has been changed. For example, under "odd parity" the number of 1 bits sent for each character must be odd; the parity bit is set to either 1 or 0 in order to make the count come out odd. If, upon receiving the character, the number of 1 bits is even, you know that at least one of them was changed (unfortunately, you don't know which one it was). For "even parity", the parity bit is set so that the number of 1 bits sent is an even number. Both sender and receiver must agree on what parity is being used!
M. Parallel Processing means many computers working on the same problem.

TRUE. The speed of light limits the speed that electronic computer circuits can switch, so single computers have upper limits on how fast they can solve problems. Having more than one computer working on the same problem at the same time gets around these upper limits. A major problem in Computer Science research is on the techniques needed to get all of these separate computers to coordinate and communicate with each other properly!
N. A pixel is the smallest spot on the screen where the color can be changed

TRUE. Pixel stands for "picture element" (another abbreviation that you may see is "pel"), and it is the smallest dot in graphics mode that a program can set to a unique color.

#2 -- Convert the following numbers (show your work, and NO calculators allowed!)

A. 25 (base 10) to base 2
1. Write out "enough" powers of two:
  2^6 2^5 2^4 2^3 2^2 2^1 2^0
2. Compute them:
  64 32 16 8 4 2 1
3. Discard all greater than 25:
  16 8 4 2 1
4. Starting at the left, fill in the digits:
  16 fits 1 time, subtract 16 from 25 leaving 9
  8 fits 1 time, subtract 8 from 9 leaving 1
  4 fits 0 times
  2 fits 0 times
  1 fits 1 time, subtract 1 from 1 leaving 0
5. Write down the digits:
  11001 (base 2)
6. Verify:
  1*16 + 1*8 + 0*4 + 0*2 + 1*1 = 16+8+1 = 25
B. 57 (base 10) to base 2
As above: 111001 = 1*32 + 1*16 + 1*8 + 0*4 + 0*2 + 1*1 = 57
C. 11001010 (base 2) to base 10
1*128 + 1*64 + 0*32 + 0*16 + 1*8 + 0*4 + 1*2 + 0*1 =
128 + 64 + 0 + 0 + 8 + 0 + 2 + 0 = 202 (base 10)
D. 11001011 (base 2) to base 10
1*128 + 1*64 + 0*32 + 0*16 + 1*8 + 0*4 + 1*2 + 1*1 =
128 + 64 + 0 + 0 + 8 + 0 + 2 + 1 = 203 (base 10)
Notice that the binary number in this problem is only one greater than the binary in problem C; by recognizing this fact you could simply add 1 to the decimal result of problem C without performing a conversion: 202+1=203.
E. 204 (base 5) to base 10
2*(5^2) + 0*(5^1) + 4*(5^0) =
2*25 + 0*5 + 4*1 =
50 + 0 + 4 = 54 (base 10)
F. 152 (base 9) to base 10
1*(9^2) + 5*(9^1) + 2*(9^0) =
1*81 + 5*9 + 2*1 =
81 + 45 + 2 = 128 (base 10)
G. 89 (base 10) to base 18
By doing the standard analysis, you come up with an expansion of 4*(18^1) + 17*(18^0)
Writing down "417" is wrong because the "17" really represents a single digit. You must map digits greater than 9 into the appropriate letters: A=10, B=11, C=12, D=13, E=14, F=15, G=16, H=17. So the correct answer is 4*(18^1) + H*(18^0), or 4H (base 18).
H. 55 (base 10) to base 19
This is similar to problem G. Find the expansion 2*(19^1) + 17*(19^0) and map any digits greater than 9 into letters to get the result 2H (base 19).

#3 -- Convert the binary number 111011010 to base 8 without converting it to base 10 first (show how the binary number is partitioned into bits before the conversion

Since 2^3 = 8^1, every three binary (base 2) digits is equivalent to one octal (base 8) digit. Starting at the right, partition the binary number into packets of three bits and treat each packet of three bits as if it were a separate (much smaller) conversion problem. (If you get to the left side of the binary number and fewer than three bits remain, pad to the left with zeroes until you get three bits -- remember that leading zeroes don't affect the result.) For this problem, the partitions give you bit packets: 111 011 010

Convert 111 to decimal: 1*2^2 + 1*2^1 + 1*2^0 = 4+2+1 = 7
Convert 011 to decimal: 0*2^2 + 1*2^1 + 1*2^0 = 0+2+1 = 3
Convert 010 to decimal: 0*2^2 + 1*2^1 + 0*2^0 = 0+2+0 = 2

Once you have made all of the conversions, write down the digits in order:

732 (base 8)

If the problem were to convert the number into hexadecimal (base 16), the only part that differs from above is the number of bits in each packet. Since 2^4 = 16^1, every four bits is the same as one hexadecimal digit. Partitioning the binary number gives us (notice that we had to pad the left packet with three zeroes):

0001 1101 1010

Convert 0001 to decimal: 0*2^3 + 0*2^2 + 0*2^1 + 1*2^0 = 1
Convert 1101 to decimal: 1*2^3 + 1*2^2 + 0*2^1 + 1*2^0 = 13
Convert 1010 to decimal: 1*2^3 + 0*2^2 + 1*2^1 + 0*2^0 = 10

After all conversions, write down the digits in order, mapping digits greater than 9 onto the appropriate letters (A=10, B=11, C=12, D=13, E=14, F=15):

1DA (base 16)

#4 -- To convert a binary number directly to a base which is a power of two (base 4, 8, 16, 32, etc.) without going through decimal, partition the number into groups, then convert each group individually. How many bits are in each group if you are converting to:

A. Base 8 Three, since 2^3 = 8^1
B. Base 16 Four, since 2^4 = 16^1
C. Base 32 Five, since 2^5 = 32^1

#5 -- A word in computer jargon is defined as two consecutive bytes of memory. How many...

In this problem, you must remember that there are 8 bits in a byte, and that "kilo" means 2^10 = 1024 when talking about computer memory. So, a "kiloX" means 1024 X's, whatever an X is.

A. Bits in a word?
(8 bits per byte) * (2 bytes per word) = (16 bits per word)
B. Bytes in 2 kilobytes?
(2 kilobytes) * (1024 bytes per kilobyte) = 2048 bytes
C. Bytes in 2 kilowords?
(2 kilowords) * (1024 words per kiloword) * (2 bytes per word) = (2 * 1024 * 2) = 4096 bytes
D. Words in 2 kilobits?
(2 kilobits) * (1024 bits per kilobit) / (16 bits per word) = (2 * 1024 / 16) = 128 words
E. grams in a kilogram? (grams have nothing to do with computers!)
Trick question: 1000 grams per kilogram.

#6 -- A quad is defined as four consecutive bytes of memory. How many.....

As in the previous problem, this involves computer memory, where "kilo" means 1024. When performing conversions, you need to know whether to multiply one unit by another or divide. If you are going from lots of little units (e.g., bits) to fewer big units (bytes, nybbles, words, quads, etc.) you divide. If you are going in the other direction you multiply to get a large number of smaller units.

A. Bits in a quad?
(8 bits per byte) * (4 bytes per quad) = (32 bits per quad)
B. Bytes in 5 kiloquads?
(5 kiloquads) * (1024 quads per kiloquad) * (4 bytes per quad) = (5 * 1024 * 4) = 20480 bytes
C. Bits in 5 kiloquads?
(5 kiloquads) * (1024 quads per kiloquad) * (32 bits per quad) = (5 * 1024 * 32) = 163840 bits
(5 kiloquads) * (1024 quads per kiloquad) * (4 bytes per quad) * (8 bits per byte) = (5 * 1024 * 4 * 8) = 163840 bits
D. Quads in 5 kilobits?
(5 kilobits) * (1024 bits per kilobit) / (32 bits per quad) = (5 * 1024 / 32) = 160 quads

#7 -- Think about one digit from the seven segment display on your pocket calculator; you can light the segments to form a lot more characters than simply 0 through 9 (think about A, C, and E, for example). How many different patterns of lighting can you set up on one display digit? (you may express your answer as a power; you don't need to calculate it.)

Each digit has seven segments, each segment may be either on or off. In some sense, then, the display represents a seven digit binary number (1=on, 0=off), and the problem becomes "how many different numbers can you generate with seven binary digits?". Study pages 25-27 of the workbook. From that you will see that the number of patterns is b^d, where b is the base and d is the number of digits. For this problem, b=2 and d=7, so you can get 2^7 = 128 different patterns on one display digit. (With one segment you have two patterns, one and off. With two segments you have four: off-off, off-on, on-off, and on-on. Every time you add a segment you double the number of possible patterns.)

#8 -- A family has four children, each with a red shirt, a green shirt, and a blue shirt. How many configurations of children and shirts are possible?

This is the same kind of problem as #7. You must determine the base (number of possibilities per digit) and the number of digits (the independent variables). In this case, the children are independent, so the number of digits is four. The base is three because each child has one of three choices for shirts. Since b=3 and d=4, b^d = 3^4 = 81 combinations.

#9 -- Suppose I give you a 5-input AND gate.....

A. How many rows would its corresponding truth table contain?
This is also similar to the last two problems. With five input lines, each of which may be either 0 or 1, we have a problem with 5 base 2 digits, b=2 and d=5 means that there will be 2^5 = 32 rows in the truth table (from 00000, 00001, 00010, 00011, ... , 11111).
B. How many entries in that truth table would contain an answer value of 1?
Since the gate is an AND gate (where the output is 1 only when all inputs are 1, and 0 when any input is 0), and since only one row in the truth table has all input values equal to 1, only one of the 32 possible outputs will be 1. This will be true for any AND gate, no matter how many inputs it has: the output will be 1 if all inputs are 1 and 0 otherwise.
If I asked the question about OR gates instead of AND gates, the analysis would be similar: OR gates output a 1 if any input is 1 and output 0 only if all inputs are 0. For a 5 input OR gate, one output will be 0 and 31 outputs will be 1.

#10 -- Trace the following circuit and show the outputs for all possible input values

A=0, B=0:
NOT sees 0 from input A, outputs 1,
NOR sees 1 from NOT, 0 from input B, outputs 0,
NAND on top sees 0 from both inputs A and B, outputs 1,
final NAND sees 1 from top NAND, 0 from NOR, outputs 1.
A=0, B=1:
NOT sees 0 from input A, outputs 1,
NOR sees 1 from NOT, 1 from input B, outputs 0,
NAND on top sees 0 from input A, 1 from input B, outputs 1,
final NAND sees 1 from top NAND, 0 from NOR, outputs 1.
A=1, B=0:
NOT sees 1 from input A, outputs 0,
NOR sees 0 from NOT, 0 from input B, outputs 1,
NAND on top sees 1 from input A, 0 from input B, outputs 1,
final NAND sees 1 from top NAND, 1 from NOR, outputs 0.
A=1, B=1:
NOT sees 1 from input A, outputs 0,
NOR sees 0 from NOT, 1 from input B, outputs 0,
NAND on top sees 1 from both inputs A and B, outputs 0,
final NAND sees 0 from top NAND, 0 from NOR, outputs 1.

#11 -- Trace the following circuit and show the outputs for all possible input values

A=0, B=0:
NAND at left sees 0 from both inputs A and B, outputs 1,
NAND on top sees 0 from input A, 1 from left NAND, outputs 1,
NAND on bottom sees 0 from input B, 1 from left NAND, outputs 1,
AND sees 1 from top NAND, 1 from bottom NAND, outputs 1.
A=0, B=1:
NAND at left sees 0 from input A, 1 from input B, outputs 1,
NAND on top sees 0 from input A, 1 from left NAND, outputs 1,
NAND on bottom sees 1 from input B, 1 from left NAND, outputs 0,
AND sees 1 from top NAND, 0 from bottom NAND, outputs 0.
A=1, B=0:
NAND at left sees 1 from input A, 0 from input B, outputs 1,
NAND on top sees 1 from input A, 1 from left NAND, outputs 0,
NAND on bottom sees 0 from input B, 1 from left NAND, outputs 1,
AND sees 0 from top NAND, 1 from bottom NAND, outputs 0.
A=1, B=1:
NAND at left sees 1 from both inputs A and B, outputs 0,
NAND on top sees 1 from input A, 0 from left NAND, outputs 1,
NAND on bottom sees 1 from input B, 0 from left NAND, outputs 1,
AND sees 1 from top NAND, 1 from bottom NAND, outputs 1.

PART 2 -- MS-DOS Review

#12 -- In this problem, each of the descriptions below is for a task that I wish to perform as part of a sequence (each answer builds on the one before it). For each description, write down the single MS-DOS command that you would type in to perform the requested task. You may assume that you are on one of the machines in the lab, connected to the file server, and that there is a blank, formatted disk in the `A:` drive. Your prompt is `C:\>`, the default path on `F:` is `F:\`, and the default path on `A:` is `A:\` (of course since the disk in `A:` is blank).

There may be several correct answers for the questions below; in such cases the answers will be listed on separate lines.

A. Without leaving C:, create a subdirectory on A: called DOCUMENT
MD A:DOCUMENT MD A:\DOCUMENT MKDIR A:DOCUMENT MKDIR A:\DOCUMENT
Since the default path on A: is at the root already, adding the backslash to force the path back to the root doesn't change anything, and is therefore optional. Remember that MD and MKDIR are synonyms.
B. Get a directory listing of the current, default drive and path (i.e., still C:\)
DIR DIR C: DIR C:\
The command DIR by itself assumes current drive (C:) and current path (\), so adding these is optional.
C. Without leaving C:, COPY the file INTER.TXT from the COINS105 subdirectory of F:\ to the (newly created) DOCUMENT subdirectory of A:
COPY F:COINS105\INTER.TXT A:DOCUMENT COPY F:\COINS105\INTER.TXT A:DOCUMENT COPY F:COINS105\INTER.TXT A:\DOCUMENT COPY F:\COINS105\INTER.TXT A:\DOCUMENT
Again, since the default path on F: is at its root, adding the leading backslash is optional. Similarly, since DOCUMENT is one level down from the root of A: and the default on A: is already at the root, adding the leading backslash changes nothing.
D. Change the logged (default) disk drive to A:
A:
Note that typing A:\ doesn't do the job.
E. Change the logged (default) path to DOCUMENT
CD DOCUMENT CD \DOCUMENT CD A:DOCUMENT CD A:\DOCUMENT CHDIR DOCUMENT CHDIR \DOCUMENT CHDIR A:DOCUMENT CHDIR A:\DOCUMENT
Since the default drive is A:, adding the drive is redundant (it doesn't hurt anything). Similarly, since the A: drive is at the root, adding the backslash doesn't change the action. Finally, remember that CD and CHDIR are synonyms.
F. Without leaving A:\DOCUMENT, create a LOTUS subdirectory under A:\
MD \LOTUS MD A:\LOTUS MKDIR \LOTUS MKDIR A:\LOTUS
In this case, since the default path is below the root, the leading backslash is required (omitting the backslash would create a LOTUS subdirectory inside DOCUMENT instead of under the root). As before, the A: is optional since that is already the default drive, and MD and MKDIR are synonyms.
G. Without leaving A:\DOCUMENT, change the path on F: to \COINS105
CD F:COINS105 CD F:\COINS105 CHDIR F:COINS105 CHDIR F:\COINS105
Since the default path on F: is at its root, the leading backslash is optional, and CD and CHDIR are synonyms. Notice that the F: specification is required, since we need to override the default drive (A:). When this command is complete, the default drive is still A: and the default path is still \DOCUMENT.
H. Create a subdirectory of A:\DOCUMENT called GLOP
MD GLOP MD A:GLOP MD A:\DOCUMENT\GLOP MKDIR GLOP MKDIR A:GLOP MKDIR A:\DOCUMENT\GLOP
Since the default path is already in the place where the new subdirectory will be created, the best solution is simply MD GLOP. The A: drive specification is optional, and MD and MKDIR are synonyms.
Note that although MD A:GLOP is legal, MD A:\GLOP is illegal in this circumstance because GLOP would be inserted off of the root instead of inside DOCUMENT.
I. Oops! Didn't want that subdirectory here! Get rid of the GLOP subdirectory
RD GLOP RD A:GLOP RD A:\DOCUMENT\GLOP RMDIR GLOP RMDIR A:GLOP RMDIR A:\DOCUMENT\GLOP
Exactly the same analysis as above (RD A:GLOP is legal but RD A:\GLOP is not), except that we are removing a subdirectory instead of creating one, and RD and RMDIR are synonyms.
J. Take a breather, and clear the screen.
CLS
K. You are in A:\DOCUMENT. Show the contents of INTER.TXT on the screen.
TYPE INTER.TXT TYPE A:INTER.TXT TYPE A:\DOCUMENT\INTER.TXT
Back in step C we copied the INTER.TXT file into the A:\DOCUMENT subdirectory, which just happens to be the default. The command TYPE INTER.TXT is simplest, but the command TYPE A:\DOCUMENT\INTER.TXT will work from anywhere, regardless of the current drive and path.
L. Without leaving A:\DOCUMENT, copy INTER.TXT to the root of A:
COPY INTER.TXT \ COPY A:INTER.TXT A:\ COPY A:\DOCUMENT\INTER.TXT A:\
Since the default path is where the file is currently located, the path is optional. The source drive and destination drive are both the default, so they are optional as well, leading to the strange looking case of an isolated backslash as the destination (the first possible answer), meaning the "root of the current drive".
M. Delete the INTER.TXT file in the current (default) directory.
DEL INTER.TXT DEL A:INTER.TXT DEL A:\DOCUMENT\INTER.TXT ERASE INTER.TXT ERASE A:INTER.TXT ERASE A:\DOCUMENT\INTER.TXT
Again, we can use the default drive and path, or fully specify them. Note that DEL A:\INTER.TXT will delete the wrong copy (the one at the root). The synonym for DEL is ERASE, not DELETE (no such critter).
N. Change the default directory to the root of A:
CD .. CD \ CD A:.. CD A:\
Normally, CD \ is the preferred answer, but since the current path is only one level down from the root, the command CD .. will also work (it would not work if the current path was any deeper than one level). As before, the drive specification is optional here.
O. Rename INTER.TXT so it is now called INTERNET.TXT instead.
REN INTER.TXT INTERNET.TXT RENAME INTER.TXT INTERNET.TXT
The commands REN and RENAME are synonyms.

#13 -- Two files called FILEA.WRI and FILEB.WRI are in the current subdirectory of my disk. FILEA.WRI contains the data that should be in FILEB.WRI, and vice versa.

Using only the RENAME command, help me straighten out this mess
What we can't do is rename FILEA to FILEB, then FILEB to FILEA. If we had two glasses full of juice that we wanted to exchange, what do we need? A third glass! We need a third filename here:
RENAME FILEA.WRI TEMP RENAME FILEB.WRI FILEA.WRI RENAME TEMP FILEB.WRI
Do the same task using only the COPY and DEL commands.
We approach the problem in the same manner here as above, recognizing that if we copy one file to another where the destination doesn't exist it is created, and if it already exists, it is replaced by the file being copied. Once the swap is complete, we need to delete the extra file hanging around:
COPY FILEA.WRI TEMP COPY FILEB.WRI FILEA.WRI COPY TEMP FILEB.WRI DEL TEMP

#14 -- You are working in Windows Write on a document. In order to keep old versions, you successively save your document to unique files where the names contain an increasing number. These files are called (successively) FILE0001.WRI, FILE0002.WRI, FILE0003.WRI, and so on.

A. You realize that your current version, FILE0175.WRI, is completely wrong. What MS-DOS command would you type to get rid of this single file?
DEL FILE0175.WRI
B. What single MS-DOS command would you type in to get rid of all files from FILE0001.WRI through FILE0099.WRI, inclusive?
DEL FILE00??.WRI DEL FILE00*.WRI Since the files are the same up through the first six characters, we can use wildcards (? or *) to match the two characters that differ.

#15 -- In MS-DOS, what is the difference between an internal command (such as `CLS`, `CD`, `DEL`, and `RD`) and an external command (such as `FORMAT`, `CHKDSK`, or `WIN`)?

Internal commands are those that you absolutely need in order to manage the files on your disks, and as such are built into the operating system running in RAM so as to be always available. When you type in a command at the MS-DOS prompt, DOS first looks through its internal list to see if the command you typed is present; if so the command is executed immediately from the code running in RAM. If not, then MS-DOS looks around on the disk drives for a program file with the same name as the command, but ending in one of the extensions .BAT, .COM, or .EXE. Upon finding such a file, the file is loaded into RAM from the disk, run, then flushed from RAM (if no file with that name is found, then you get the error message "BAD COMMAND OR FILE NAME"). This is a neat way of extending the operating system so that to a user it looks like all the needed commands are built in, even those that the writers of MS-DOS could not anticipate.

For a short "exam answer", state that internal commands are built into MS-DOS and are always available, while external commands are program files that must be loaded in from disk before they can be run.

#16 -- What are the three major functions of an operating system?

To manage the hardware
Computers have peripheral devices (tape drives, disk drives, keyboards, modems, printers, etc.), so when services from one or more of these are required, the operating system makes sure that they are healthy and available. In a multi-user computing system (such as UNIX) the operating system is responsible for arbitrating requests for hardware from different users, so that everybody gets a fair chance at using the equipment. (For example, suppose that a system had four tape drives and two individual users each wanted three tape drives at the same time. The operating system has to make sure that one user doesn't just grab and hold the drives without letting the other user have a chance, and it must insure that both users don't grab two drives and lock each other out from the third.)
To provide a user interface
Whether it is a GUI (graphical user interface) such as the Mac or one of the varieties of Windows, or a CLI (command line interface) such as DOS or UNIX, the operating system has to provide some mechanism for allowing users to enter commands and see their results.
To allow users to run programs, including user programs
Using a computer means running programs, whether those written by the "wizards" who set up the system, or the "ordinary mortals" who have to use it.

#17 -- You have a blank, formatted disk in A:, and the prompt is `A:\>`. To the right, write down all commands necessary to construct the directory structure shown.

(The root of A: has subdirectories MONEY and JUNK hanging from it, and MONEY has subdirectories GLOP and JUNK hanging from within it.)

MD MONEY
MD JUNK
MD MONEY\GLOP
MD MONEY\JUNK

Since there are only four slots for answers, and four subdirectories that must be created, all four commands must be variants of the MD command. Therefore, you can't create MONEY and then CD MONEY in order to create the inner subdirectories (that would take a fifth command). Hence, you must include the path information for the commands that create the inner subdirecotries.

#18 -- Assume that you successfully built the directory structure above. For all questions below, assume that the prompt is `A:\MONEY>` (all questions are independent).

A. What is the prompt after the command CD GLOP is entered?
A:\MONEY\GLOP>
B. What is the prompt after the command CD JUNK is entered?
A:\MONEY\JUNK>
Since we are in MONEY and there is no path information in the command that we typed, the inner JUNK subdirectory is assumed.
C. What is the prompt after the command CD \JUNK is entered?
A:\JUNK>
The leading backslash takes us up to the root, and then into the JUNK hanging there.
D. What is the prompt after the command CD ..\JUNK is entered?
A:\JUNK>
The .. takes us up one level, which happens to be to the root, then down into the JUNK hanging there. This is an inefficient way of doing the same thing as in part C.
E. What is the prompt after the command CD GLOP\..\JUNK is entered?
A:\MONEY\JUNK>
This command first takes us down into GLOP, then the .. brings us right back to where we started (MONEY), then into the JUNK hanging from MONEY.
F. What is the prompt after the command CD \MONEY\JUNK is entered?
A:\MONEY\JUNK>
This command traces the complete, absolute path from the root (the leading backslash) through MONEY and into the innermost JUNK.
G. What command would I type to get rid of the GLOP subdirectory?
RD GLOP
H. What command would I type to change the prompt to the root of A:?
CD ..
CD \
Since MONEY is only one level down from the root, these two commands have the same effect. If we were at the root the CD .. command would not work at all, and if we were more than two levels down the CD .. command would not bring us up far enough to reach the root.

#19 -- A new command called `BUBBLE` is available. `BUBBLE` works exactly the same way that the `DIR` command does, except that instead of displaying the files in the directory it counts the number of matching files (not including the special subdirectories `.` and `..`) and then displays that many "bubbles" on the screen. Just as in the `DIR` command, the `BUBBLE` command may use the `` and `?` wildcard characters. For example, if I type in the regular command `DIR A:\COINS105\FALL1992\.DOC` then the file names printed out would be `LAB1.DOC`, `LAB2.DOC`, `LAB3.DOC`, and `LAB4.DOC`. By contrast, the new command `BUBBLE A:\COINS105\FALL1992\*.DOC` would answer with `oooo` (4 bubbles). Using `BUBBLE`, and the directory tree drawn below, give commands to display on the screen exactly:

(In several cases where many answers are legal an assortment is given.)

One Bubble o (many answers)
BUBBLE A:\TEMP.DAT
BUBBLE A:\TAXES\EXCUSE.DOC
BUBBLE A:\TAXES\EXCUSE.BAK
BUBBLE A:\WORD\BUDCLARK.DOC
etc.
Two Bubbles oo
BUBBLE A:\TAXES\EXCUSE.*
BUBBLE A:\WORD\*.DOC
BUBBLE A:\WORD\SAMPLE.*
BUBBLE A:\TAXES\1991\*.WK1
etc.
Three Bubbles ooo
BUBBLE A:\WORD\*.*
BUBBLE A:\TAXES\1991\*.*
BUBBLE A:\COINS105\SPR\*.DOC
Four Bubbles oooo
BUBBLE A:\COINS105\SPR\*.*
BUBBLE A:\COINS105\FALL1992\*.DOC
Five Bubbles ooooo
BUBBLE A:\COINS105\FALL1992\*.*

#20 -- How many bubbles will be displayed by the command below? `BUBBLE A:\TAXES\1991\*.WK1`

Two. One bubble for REPLY.WK1 and one for RESEARCH.WK1 (only two files have .WK1 extensions).

#21 -- What single MS-DOS command will erase all files in the `\WORD` subdirectory?

DEL \WORD\*.* will do the job. You may use the synonym ERASE for the DEL command, and you may include the A: as part of the path, even though it is not required.

PART 3 -- Microsoft Windows

#22 -- What advantages do a Graphical User Interface (GUI) such as Microsoft Windows have over a Command Line Interface (CLI) such as MS-DOS?

In a CLI you must remember all of the possible commands, as well as any modifiers, and must type them in exactly or they will not work correctly. In a GUI all available commands are presented as a list of menu items or push buttons. In essence, CLI's are "fill in the blank", and GUI's are "multiple choice".

#23 -- In a Windows dialog box, what is the difference between a set of check-boxes and a set of radio-buttons?

Although check-boxes are typically shown as squares and radio-buttons as circles, there is a more fundamental difference than shape. In a group of check-boxes, any or all may be checked or unchecked; they are used for selecting many options from a set of options. In a group of radio-buttons, only one may be selected at any one time; selecting another unselects the previously selected button. This is similar to the car radios which have a set of buttons for finding preset stations quickly; pushing in one button pops out the one that was pushed in.

#24 -- Please write a single sentence to define each of the following terms:

A. icon
A small picture that represents a specific program or a group containing many program icons.
B. group icon
An icon in Program Manager that holds a group of related program icons (a program icon is an icon that is "attached to" a program file -- double click a program icon to run the program).
C. scroll bar
A region along the right-hand side or bottom of a window that indicates that more material is off the screen. The scroll bar along the right-hand side of the window scrolls the window vertically, while the scroll bar along the bottom scrolls the window horizontally.
D. clipboard
A "holding area" in Windows for containing a bit of text or graphics being moved or copied from one application (or position within an application) to another. The contents of the clipboard are not saved when Windows exits, are replaced by new material when a new Cut or Copy is performed, and are not erased when pasted (allowing for multiple Pastes).
E. multitasking
The ability to run more than one program so that it appears that all of the programs are running simultaneously. The operating system switches between each of the programs quickly enough that you don't see the times when they are not running.

#25 -- Based on the views above, most of your answers to the questions below will be like "Click on the _ button", "Click on the _ menu entry", "Double click on the _ icon", or "Click-drag on the _ control" (filling in the blank appropriately).

A. How do we open the Accessories group (going from BEFORE to AFTER)?
Double click on the Accessories group icon.
B. How do we close the Accessories group (going from AFTER to BEFORE)?
Either click on the Accessories window's minimize button (in the upper right corner of the window) or douoble-click on its File-Control button (in the upper left corner of the window), or click on the File-Control menu and then click on the Minimize entry in the menu that pops up.
C. In either view, how do we make Program Manager fill the entire screen?
Either click on its maximize button (in the upper right corner of the window), or click on the File-Control button and then click on the Maximize entry in the menu that pops up.
D. In the BEFORE view, how do we collapse Program Manager to an icon?
Either click on its minimize button, or click on the File-Control button and then click on the Minimize entry in the menu that pops up.
E. In the BEFORE view, if I press Enter, what group window will open?
The Mouse group will open, since it is already selected (the text under its icon is highlighted).
F. In the AFTER view, are there more Accessories than are visible right now?
Yes. You can tell because of the presence of the vertical scroll bar. The position of the thumb button at the top of the scroll bar tells you that the other program icons are below the visible icons.
G. In the AFTER view, how do we start running a copy of Calculator?
Double-click on the Calculator icon.
H. In the AFTER view, I want to see other Program Manager groups without minimizing Accessories. How do I move the Accessories window out of the way?
Click-drag on its title bar until the window is out of the way (since it is a child-window of Program Manager, dragging it past the border of the Program Manager window will cause it to slide out of sight -- it will never appear outside of Program Manager). Notice that this problem asked to move the group window, not to change its size.
I. In the AFTER view, I want to see other Program Manager groups without minimizing Accessories. How do I make the Accessories group a bit smaller?
Click-drag on any of the edges of the window until the size is correct. Note that this problem did not ask to either minimize or move the window, just to resize it a little bit.

#26 -- Short answer. What is a group icon, and how is it used?

A group icon is an icon that exists inside of Program Manager, and is used to contain program icons. Typically, the program icons within a group icon are related in some general way.

#27 -- For these questions, please refer to the screen image just above:

A. Which is the active application?
Calculator is the active application. You can tell this because it has the dark title bar. Yes, it is in front of the Windows Write window, but in cases of two or more windows that do not overlap the title bar is the only way you can tell which application is active.
B. How do I bring the Windows Write document to the top in one mouse click?
Click on its title bar. Note that if you click anywhere in the body of the document, you will also bring the window to the top, but the insertion point will be moved to the position of the mouse click. Clicking on the title bar makes the application active without moving the insertion point.
C. How do I move the Calculator window out of the way without minimizing it?
Click-drag its title bar until its window no longer overlaps that of the Windows Write window.
D. How do I put the calculator's number into the document without retyping it?
First, click Edit-Copy in Calculator. Second, activate the Windows Write window and set the insertion point to where the number is to be inserted. Finally, click Edit Paste in the Windows Write window.

PART 4 -- Word Processing & Windows Write

#28 -- Must you highlight an entire document before saving it? Why or why not?

No. I've had some people believe that they had to select the whole document in order to save the whole document, and in some way that makes a certain kind of sense. However, the File-Save menu entry assumes that the entire document is to be saved. In order to save a fragment of a document, you would have to create a separate document containing only that fragment (by cut and paste), then save that separate document.

#29 -- What is the difference between saving a document and printing it to a file?

This is an exercise that you did in lab 2; you printed your document to a file, then copied the file to the printer. This is to illustrate that you can "print" without actually having a printer available, then take your file to a computer that has a printer (but not necessarily a word processor). This also help us in those cases where the lab computers are working but not the printer -- you can do all of your work, including the print step, then come back when the printer is up to copy the results to paper. For many years, I had no printer at home: I would print my documents to files, then shove the files up through the modem to computers in my department that were attached to good printers. Those departmental computers not only did not know anything about how my document was formatted, they weren't even PC's!

Saving a document in the normal way (File-Save) saves the text along with formatting commands (which characters are bold face, which are italic or underlined, paragraph styles, document layout styles, font information, etc.). Typically, this file does not contain information about a specific type or brand of printer.

Printing to a file converts the document into a series of commands that tell a specific type of printer how to place marks on a page. When the file is copied to the printer, the printer has no way of telling that it is receiving its information from a file and not from a File-Print menu command.

#30 -- Short Answer: what is kerning, and how does it improve the look of a document?

Normally, characters do not overlap. Each character is placed directly next to its neighbors on the line. The shapes of those adjacent characters may be such that there is an awkward looking gap between them (think of a "V" followed by an "A").

Kerning allows characters to overlap in order to reduce the amount of whitespace between them. In some cases, one character may fit under an overhang of another.

Note that kerning and proportional spacing are not the same; proportional spacing means that every character takes up only the amount of space on the line that it requires ("i" takes up less space than "W"), and proportional spaced text may be either kerned or not kerned.

#31 -- Short answer: what is the difference between a typeface and a font?

A typeface is the set of common shapes that define an alphabet. In many cases, these shapes are defined by mathematical curves that can be scaled up or down, skewed, shifted, etc. A font is a typeface at a particular weight (normal, bold, thin, etc.), style (normal, italic, reverse italic, hollow, etc.), and point size. "Times Roman" is a typeface, "Times Roman, bold, italic, 12 point" is a font. Typefaces can't be printed (because you don't know size, etc.), but fonts can.

#32 -- A character font is defined by four major attributes, listed below. Define each one:

1. Typeface
The set of common (mathematical) shapes that define an alphabet.
2. Weight
The thickness of the lines (normal, bold, thin, etc.)
3. Style
Attributes such as italic (tipped over to the right), reverse italic (tipped to the left), hollow, etc.
4. Point Size
The distance between the top of the ascender region and the bottom of the descender region of a font, in points. One point is approximately 1/72 of an inch.

#33 -- Suppose that whenever you go to the Edit menu, you don't see either Cut or Copy in boldface (i.e., they are grayed out and you are not allowed to choose either one). What does this mean? What would it mean if Paste were grayed out?

If Cut and Copy are grayed out, there is nothing to either cut or copy to the clipboard. This means that nothing in the document is selected (covered by the highlight). To check this, bring up an existing Windows Write document, make sure that the insertion point is a vertical line between two characters, then click on the Edit menu -- Cut and Copy will be gray.

If Paste is grayed out, there is nothing in the clipboard to paste. This is the state that Windows is in when you first start it up, and if you click the Edit menu in an existing document before doing any cuts or copies, the Paste entry will be gray. Once you make a cut or copy, Paste will be activated for the rest of the session (remember that material remains in the clipboard until it is replaced by something new).

#34 -- Windows is running, and there are two copies of Windows Write open on the desktop. One copy contains a document called `TOP.WRI`, and the other, which is the active window, contains a document called `BOTTOM.WRI`. Describe all the steps to move (not just copy) all the text from `BOTTOM.WRI` to the bottom of the text in `TOP.WRI`.

First, select all of the text in BOTTOM.WRI (this can be done by scrolling to the top of the document, then click-dragging to the bottom, or by keyboard command Ctrl-Home followed by Ctrl-Shift-End). Next, click on Edit-Cut (because this is a move instead of a copy, you Edit-Cut instead of Edit-Paste). Next, click on the window containing TOP.WRI, and position the insertion point at the bottom of the document. Finally, click Edit-Paste.

#35 -- True or False: If you left justify a paragraph, then immediately right justify, you have performed the same action as clicking on Paragraph, then on Justify

False. The paragraph remains in the last justification mode selected, namely right justified. Full justification requires a separate menu entry.

#36 -- Word processors often have a feature called drag-and-drop. After text is selected by a click-drag, the user moves the text by clicking inside the highlight, then dragging the cursor to where the text should go. When the button is released, the text appears in the new position. Does drag-and-drop use the clipboard to hold the text being moved? Explain.

There is no need to use the clipboard because the source text and its new destination are both well defined. Drag-and-drop is most useful when both source and destination are only short distances apart (no more than a page apart, say). For longer moves, Edit-Cut and Edit-Paste (which use the clipboard) are still useful.

#37 -- Examine the following Windows Write document. Notice that the Indents dialog box is open on top of the text window. What values would you put in each of the three boxes for the requested indents?

	Left Indent	First Line	Right Indent
What are the current values of the indents?	0.0	0.0	0.0
Normal: Indent the first row by 1/2 inch	0.0	0.5	0.0
Hanging: Indent body 1/2 inch, but not first line	0.5	-0.5	0.0
Quoted: Indent both sides by 1/2 inch, not first line	0.5	0.0	0.5
Quoted: Indent both sides and first line by 1/2 inch	0.5	0.5	0.5

Remember that the First Line indent is relative to the Left Indent. A positive First Line indent moves to the right, a negative First Line indent moves to the left (see the Hanging indent example).

#38 -- Answer each question below for the corresponding screen to its left.

Notice that the cursor is between a blank and a W character. Which character is deleted if I press the Backspace key? Which character is deleted if I press the Del key instead?
Backspace deletes to the left, so it will remove the blank. Del deletes to the right, so it will remove the "W".
I want to make the text look like this. Which menu entry do you click to get the list of justifications? What type of justification was selected?
Look in the Paragraph menu for the justifications. This paragraph was formatted using Centered justification (notice that it is ragged on both left and right sides).
What type of justification was selected in this case? What happens to the paragraph if I press the Enter key?
This paragraph is fully justified (even on both left and right sides). If I press Enter, the paragraph will split into two paragraphs at the insertion point, both fully justified (since the parent paragraph was justified).
I don't see all of my text, but I know it is still there. What happened? How do I fix it so I see al of the text again?
Check the horizontal scroll bar at the bottom of the window. The thumb button is moved to the right of its normal position, scrolling the text to the left. To correct it, either click-drag the thumb button back to the left, or hit the Home key.

#39 -- Your boss puts you in front of a word processing program you've never seen before. Name at least two capabilities (beyond simply typing/editing/saving/printing the text) that Windows Write has that you also expect the new word processor to have

Word-wrap
Character formats and fonts
Paragraph formats (spacing, justification, indentation)
Document formats (margins, headers, footers, tab stops)
Ability to import graphics

#40 -- Name two things that Window Write does not have that you would expect this new word processor to have

Spell checking
Thesaurus
Grammar checking
Style sheets
Mail-merge
Equation editing
Tables
Drag-and-drop editing

#41 -- The Paintbrush accessory is running, and is behind your Windows Write document (but a portion of its window is still visible). List all steps needed to put a chunk of the graphics image into the document at the current insertion point

First, click in Paintbrush to activate it. Next, select the scissors tool. Click-drag over the desired region of the image, then Edit-Copy to place that region into the clipboard. Click on the Windows Write window, and set the insertion point to where you want the image to be placed. Finally, click on Edit-Paste in the Windows Write window to drop the image into the document.

#42 -- Short Answer. In Calculator, why is there an Edit-Copy menu entry, but no need for an Edit-Cut entry?

Edit-Copy puts the number from the calculator display into the clipboard. What would Edit-Cut mean? Put the number into the clipboard, then clear the display? There is no need for this action since the display can be cleared manually.

PART 5 -- Spreadsheets & Lotus 1-2-3

#43 -- The formula in cell `E11` is: `(E8+(1.2*$C$4)-$F7/H5+G$10)`. The formula is then copied to cell `J15`. What is the formula in `J15` after the `/Copy` is completed?

First, identify those portions of the formula that do not change. These are absolute cell addresses (with a $ prefix), constants, and arithmetic operators. If you write down that much, even if you don't know how the changeable parts actually change, you will get partial credit. The partial credit answer is: (__+(1.2*$C$4)-$F_/__+_$10)

The 1.2 doesn't change because it is a numeric constant, not a cell address. The $C$4 is an absolute cell address, and does not change under a copy. Cell addresses $F7 and G$10 are mixed addresses, partially relative and partially absolute. The relative part will change and the absolute part will not.

To complete the formula, you must figure out how the relative addresses change. Relative to cell E11, cell E8 is up three, cell H5 is right three, up six, cell $F7 is absolute column F, up four, and cell G$10 is right two, absolute row 10.

Now, relative to the target cell J15, up three is J12, right three, up six is M9, column F, up four is $F11, and right two, row 10 is L$10. The final formula is then:

(J12+(1.2*$C$4)-$F11/M9+L$10)

#44 -- The formula in cell `D7` is `(B7-14+E8$F$10/B9G$1)`. The formula is then copied to cell `G15`. What is the formula in cell `G15` after the `/Copy` is completed?

As before, identify the relative parts that will change, then write down everything else. The partial credit answer is: (__-14+__*$F$10/__*_$1)

The 14 doesn't change because it is a constant, not a cell address. The $F$10 is an absolute address, and the G$1 is mixed (The G will change but the $1 will not).

Relative to cell D7, cell B7 is left two, cell E8 is right one, down one, cell B9 is left two, down two, and cell G$1 is right three, absolute row 1.

Relative to target cell G15, left two is E15, right one, down one is H16, left two, down two is E17, and right three, row 1 is J$1. The final formula is:

(E15-14+H16*$F$10/E17*J$1)

#45 -- Why is often a bad idea to place constants inside formulae? (As in the example `(D11+D11*0.09-2.00)` which you miht have seen in the first spreadsheet lab.)

Placing constants in a formula is a bad idea because you will probably end up needing to change the constant at some point in the future. If so, you must change every formula that uses the constant. The solution is to put the constant in a cell by itself, and write all formulas that depend on it to reference the cell address instead of the literal value. Now, changing the contents of the cell updates all of the formulae automatically.

This may seem silly if all you have are a couple of formulae that use the value, but even so it is much easier to replace the contents of a cell with a new value than it is to edit a formula (and make sure that you don't mess up some other part of the formula while you are correcting the value).

#46 -- The result of the formula in cell `H12` is the number `123.456`, but the width of column `H` is 3 characters. What, exactly, will show up on screen in this cell?

The result will be *** (the cell will be filled with asterisks). Numeric results need space for the significant digits of the value and a space for the sign of the number (blank for positive, "-" for negative). In this case, that would require four spaces, not three. Since there is definitely no room in the cell to switch to scientific notation, the cell must be filled with stars to show that there is a value that cannot be displayed under the current width.

#47 -- Cell `J15` evaluates to the number `1626`. Now, why would the formula `^J15+1` return a different value from the formula `(J15+1)`?

The formula (J15+1) returns the value 1627, as you would expect. In the other formula, the leading ^ indicates that the formula represents centered text, so what you would see on screen is the string J15+1 centered in the cell. It is not a formula at all, but only superficially looks like one.

#48 -- Cell `A1` contains the formula `(A2+1)`, and cell `A2` contains the formula `(A1+1)`. What kind of error is illustrated here? What is the error message shown on screen?

Cell A1 can't know its value until A2 is computed, and cell A2 can't know its value until A1 is computed. This tail-chasing is called a "circular reference error", and is shown in Lotus 1-2-3 by the message CIRC at the bottom of the screen. One of the formulas must be changed to break the ring.

#49 -- Assume that cell `A1` contains the number 5, and cell `B1` contains 1. For each of the following formulae, write down the result that would appear on screen. Be careful in your answer to indicate the proper justification of the result in the cell.

The formula you type in:	The result you see on screen:	Explanation
`'Mary`	`Mary`	Leading quote means left justified text
`"Sam`	`Sam`	Leading double quote means right justified text
`Sam`	`Sam`	Starting with a letter is the same as starting with a single quote (left justified text)
`\=`	`=============`	The leading backslash says to repeat the following character(s) throughout the cell, regardless of the width of the cell
`(B1-2*A1)`	`-9`	Since multiplication has precedence over subtraction, after replacing the cell references with their numeric values the formula becomes `(1-(2*5)) = (1-10) = -9`. By default numbers are right justified in Lotus 1-2-3.
`B1-2*A1`	`B1-2*A1`	Since the first character is a letter, this is a simple text string, not a numeric formula to be calculated.
`@SUM(A1*2,B1,1)`	`12`	The cell arguments to the `@SUM` function are replaced by the values from the referenced cells. The formula becomes `@SUM(5*2,1,1) = @SUM(10,1,1) = (10+1+1) = 12. As before, numbers are right justified.`
`"B1+A1`	`B1+A1`	The leading double quote means that this is a text string, not a numeric formula to be calculated.

#50 -- In the following expression, put parentheses around the terms in such a way as to indicate how Lotus 1-2-3 would calculate the answer.

1 - 2 ^ 3 + 4 * 5 ^ 6 / 7 + 8 * 9

This problem indicates to put as many parentheses in the expression as possible without changing its meaning. Remember that operators of the same precedence level are evaluated from left to right. An acceptable partial answer is to show only the exponentiation and multiplication/division operators parenthesized, but a complete answer will also show how the addition/subtraction operators are parenthesized as well. The partial answer is:

1 - (2 ^ 3) + ((4 * (5 ^ 6)) / 7) + (8 * 9) The complete answer is: (((1 - (2 ^ 3)) + ((4 * (5 ^ 6)) / 7)) + (8 * 9))

#51 -- For the rest of the Lotus questions, use the spreadsheet sample given below.

	____B____	____C____	____D____	____E____	____F____
1
2		`Quarter1`	`Quarter2`	`Quarter3`	`Quarter4`
3	`Fred`	`13`	`8`	`5`	`8`
4	`Mary`	`10`	`13`	`9`	`8`
5	`Sam`	`10`	`3`	`1`	`4`
6	`Total`

A. What is the result of evaluating the formula @SUM(C4..E3)?
@SUM(C4..E3) = (C4+D4+E4+C3+D3+E3) = 10+13+9+13+8+5 = 58
The trick with any of these formulae that involve ranges is to determine the corners of the range. Imagine that you drive a nail into cell C4 and another into cell E3; the cells affected by the @SUM will be those cells in the smallest rectangular box that fits around the nails.
B. What is the result of evaluating the formula @AVG(C3..D4)?
@AVG(C3..D4) = (C3+D3+C4+D4)/4 = (13+8+10+13)/4 = 44/4 = 11
In problems such as these, I try to calibrate the answers so that you can calculate them easily without a calculator. This means that most of the time the answer will be an integer (no fraction).
C. Write a formula to go in cell A1 that finds the maximum of all existing numeric cells in the Quarter1 and Quarter2 columns, and Fred's row, only.
@MAX(C3..D5,E3..F3) or @MAX(C3..F3,C4..D5)
In this case the range to be covered by the @MAX function is not rectagular -- it is concave. The trick here is to split up the region into a list of adjacent (non-overlapping) rectangular regions, then list each region as its own range in the arguments to the function. Usually there are several correct ways to partition the region into smaller regions.
D. What is the result of evaluating the formula @SUM(B1..F2)? (Tricky)
The result is 0, since the referenced cells are either empty or contain text (which has the numeric value 0).
E. The range C3..C5 has been given the range-name QUAR1. Write a formula using QUAR1 to go in cell C6 that computes the Quarter1 total.
@SUM(QUAR1)
You use the range-name QUAR1 in place of the range itself. Without the range-name the correct formula would be @SUM(C3..C5).

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