File compression utility

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File compression utility

Name:
Date:
Class:
A

Quick Questions

Shade in the A or B circle for each question.

1. What is the main job of a file compression utility?
A It makes files smaller so they use less storage space
B It makes files bigger so they are easier to find
2. Which type of software is a file compression utility?
A Utility software (a type of system software)
B Application software such as a word processor
3. You zip a folder of photos before emailing it to a friend. Why does this help?
A The photos are automatically printed
B The smaller file can be sent faster
4. What does 'unzipping' a compressed file do?
A It restores the file to its original form so it can be used
B It permanently deletes the file from the computer
5. A student's USB drive is almost full. Which utility could help them fit more files on it?
A A firewall
B A file compression utility
B

Match the Pairs

Draw a line connecting each item on the left to its match on the right.

Left columnRight column
1zip report.docx ACompresses a file into a smaller zip archive so it uses less storage space
2unzip photos.zip BCompression makes a file smaller, not bigger; the smaller size is what makes it faster to send
3A compression utility reduces file size so a file can be sent faster over a network CRestores the compressed files to their original form so they can be used again
4Compression saves storage space by making many files take up less room on a disk DA compressed file must be unzipped (restored) with the compression utility before it can be used normally
5Zip a file, then open it without unzipping it first Ezip archive.zip file1.txt file2.txt file3.txt
6Zipping makes a file bigger but faster to send Fzip holiday_video.zip video.mp4 -> email
C

Definitions

compression utility
D

Fill in the Blanks

Complete each line of code by filling in the missing parts.

1.
________ bigFile TO smallFile
2.
UNZIP archive __ originalFile
3.
IF compressedSize _ originalSize THEN OUTPUT "Space saved" ENDIF
4.
compressed ← COMPRESS(photo) SEND(__________)
5.
_____(archiveZip)
E

Spot the Error

Shade in the letter of the line that contains an error.

Question 1
A originalSize ← 50
B zipped ← compress(photo)
C zippedSize ← 80
D saved ← originalSize - zippedSize
Question 2
A IF storageFull = TRUE
B compress(videoFile)
C ENDIF
Question 3
A archive ← "photos.zip"
B files ← compress(archive)
C OUTPUT files
Question 4
A FOR i ← 1 TO 3
B compress(file[i])
C ENDIF
Question 5
A fileSize ← 100
B sendTime ← fileSize * speed
C compressedSize ← 40
D newTime ← compressedSize / speed

Answer Key

File compression utility
Section A: Quick Questions
Q1
A — It makes files smaller so they use less storage space
Q2
A — Utility software (a type of system software)
Q3
B — The smaller file can be sent faster
Q4
A — It restores the file to its original form so it can be used
Q5
B — A file compression utility
Section B: Match the Pairs
Q1
zip report.docx → Compresses a file into a smaller zip archive so it uses less storage space
Q2
unzip photos.zip → Restores the compressed files to their original form so they can be used again
Q3
A compression utility reduces file size so a file can be sent faster over a network → zip holiday_video.zip video.mp4 -> email
Q4
Compression saves storage space by making many files take up less room on a disk → zip archive.zip file1.txt file2.txt file3.txt
Q5
Zip a file, then open it without unzipping it first → A compressed file must be unzipped (restored) with the compression utility before it can be used normally
Q6
Zipping makes a file bigger but faster to send → Compression makes a file smaller, not bigger; the smaller size is what makes it faster to send
Section C: Definitions
Q1
compression utility — Utility software that makes files smaller to save storage space and send them faster, and can restore (unzip) them to their original form when needed.
Section D: Fill in the Blanks
Q1
COMPRESS bigFile TO smallFile
Q2
UNZIP archive TO originalFile
Q3
IF compressedSize < originalSize THEN OUTPUT "Space saved" ENDIF
Q4
compressed ← COMPRESS(photo) SEND(compressed)
Q5
UNZIP(archiveZip)
Section E: Spot the Error
Q1
C — A compressed file should be smaller than the original (50), so 80 is wrong. Compression makes files smaller, so the size should be less than 50, for example 20.
Q2
A — The IF statement is missing THEN. It should be IF storageFull = TRUE THEN, so the video is compressed to free up storage space when storage is full.
Q3
B — To restore the files from a zip archive you need to unzip it, not compress it again. The line should be files ← unzip(archive).
Q4
C — A FOR loop is closed with NEXT i, not ENDIF. ENDIF is used to close an IF statement.
Q5
B — Time to send a file is the size divided by the speed, so it should be fileSize / speed. A smaller compressed file therefore sends faster.