Why Linux powers the internet in Linux CLI - Test Your Understanding

Practice - 5 Tasks

1fill in blank

easy

Complete the command to list all files including hidden ones in a directory.

Linux CLI

ls [1]

Drag options to blanks, or click blank then click option'

A-a

B-l

C-h

D-r

Attempts:

3 left

💡 Hint

Common Mistakes

Using -l shows details but not hidden files.

Using -h is for human-readable sizes, not listing hidden files.

The -a option shows all files, including hidden ones starting with a dot.

2fill in blank

medium

Complete the command to find the current working directory.

Linux CLI

[1]

Drag options to blanks, or click blank then click option'

Apwd

Bls

Ccd

Dwhoami

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'ls' lists files but does not show current directory.

Using 'cd' changes directory but does not show it.

The pwd command prints the current directory path.

3fill in blank

hard

Fix the error in the command to display the first 5 lines of a file named 'log.txt'.

Linux CLI

head [1] log.txt

Drag options to blanks, or click blank then click option'

A-f 5

B-5

C-n 5

D-l 5

Attempts:

3 left

💡 Hint

Common Mistakes

Using '-5' is not a portable option for head.

Using '-f' is for following a file, not line count.

The correct option is -n 5 to specify the number of lines.

4fill in blank

hard

Fill both blanks to create a dictionary comprehension that maps words to their lengths only if length is greater than 3.

Linux CLI

{word: [1] for word in words if [2]

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Alen(word)

Bword > 3

Clen(word) > 3

Dword

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'word > 3' compares strings to numbers, which is invalid.

Not using len() to get word length.

The dictionary maps each word to its length using len(word). The condition filters words with length greater than 3 using len(word) > 3.

5fill in blank

hard

Fill all three blanks to create a dictionary comprehension that maps uppercase words to their lengths only if length is greater than 4.

Linux CLI

{ [1]: [2] for word in words if [3] }

Drag options to blanks, or click blank then click option'

Aword.upper()

Blen(word)

Clen(word) > 4

Dword.lower()

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'word.lower()' instead of uppercase.

Not using len() to get length.

Using wrong comparison operators.

The dictionary keys are uppercase words using word.upper(). Values are lengths with len(word). The condition filters words longer than 4 characters with len(word) > 4.