CH9

Question 1

Compression of a file works by?

Eliminating gaps within the file
Consolidating multiple files into one.
Removing redundant information
Storing most of the data on removable media and just leaving a pointer
Removing the high order bit from each byte

Answer 1

Removing Redundant Information

Question 2

In general, for which of the following would you want to use Lossless Compression?

MP3 Audio File
An Encrypted Email
A JPEG Image
A Log File
A Movie

Answer 2

A Log File

Question 3

Lossy Compression? (Choose Three)

Usually results better compression than lossless
Is often used with Images
Is often used with Documents
Decompresses to an identical version as the original
Sacrifices some quality

Answer 3

Usually results better compression than lossless
Is often used with Images
Sacrifices some quality

Question 4

You type gzip myfile.tar. What happens? (Choose Two)

myfile.tar is unarchived into the current directory
An error; you forgot to pass the name of the output file
myfile.tar.gz holds a compressed version of myfile.tar
An error; you forgot to specify the file with -f
myfile.tar is removed

Answer 4

myfile. tar.gz holds a compressed version of myfile.tar

myfile. tar is removed

Question 5

How would you obtain output similar to the following?
compressed uncompressed ratio uncompressed_name278168 1016950 72.6% tags

gzip -l tags
gunzip -t tags
file tags

Answer 5

gzip -l tags

Question 6

Which command will show you what is inside the compressed tarball with the name of foo.tar.gz?

tar -tif foo.tar.gz
tar -lf too.tar.gz
tar -tf foo.tar.gz
tar -xf foo.tar.gz
tar -tzf foo.tar.gz

Answer 6

tar -tzf foo.tar.gz

Question 7

Given a file called documents.zip, how can you see what’s in it without extracting the files?

zip -lf documents.zip
unzip -l documents.zip
unzip -list documents.zip
zip -l documents.zip
showzip documents.zip

Answer 7

unzip -l documents.zip

Question 8

The three main modes of TAR are? (Choose Three)

List
Create
Compress
Copy
Extract

Answer 8

List
Create
Extract

Question 9

Which two programs use the Lempel-Ziv-Markov chain algorithm? (Choose Two)

xz
lossless
lossy
bzip
gzip

Answer 9

xz

gzip

Question 10

By default, the ZIP command replaces uncompressed files with compressed files?

True
False

Answer 10

False