Coreutils

Question 1

rm

Answer 1

Removes file and directories. Does not remove directories by default.

Question 2

cat

Answer 2

Prints files or standard input to screen

Question 3

tac

Answer 3

Prints files or standard input to screen in reverse. Line by line is the default

Question 4

nl

Answer 4

Prints files or standard input to screen but adds line numbers. Cat -n is better.