Week1

Which command displays the last 20 lines of a file named `log.txt`?

• tail -n 20 log.txt
• head -n 20 log.txt
• less log.txt
• cat log.txt

How do you count the number of lines in a file?

• grep -l file.txt
• wc -l file.txt
• count file.txt
• lines file.txt

What will the command `mkdir -p /data/project/results` do?

• Make a directory only if it doesn’t already exist
• Create nested directories if they don’t exist
• Prompt for confirmation before creation
• Change to the `/data/project` directory

What is the purpose of the `>` symbol in the command `echo "Hello" > output.txt`?

• Appends text to a file
• Sends output to another command
• Redirects output to a file, overwriting it
• Displays output on screen

You ran `rm *` by mistake. What happens?

• Nothing, it asks for confirmation
• All files in the directory are deleted
• The entire OS is wiped
• Hidden files are deleted

Which command shows hidden files in a directory?

• ls -h
• ls -a
• ls --all
• Both B and C

What does the Linux command pwd do?

• Shows the current working directory

• Deletes a directory

• Lists files in a directory

• Creates a new folder

What is the purpose of the chmod command?

• Change file permissions

• Display file contents

• Delete a file

• Create a new directory

What does `cd ../..` do?

• Goes to the home directory
• Goes up one level
• Goes up two directory levels
• Goes to the root directory

What does the wildcard * represent in Linux commands?

• Only one character

• Any number of characters

• A specific file name

• A directory only