grep command written test questions

The grep command is a powerful text search tool that uses Regular ExpressionSearch Text

Print the line containing 'root' in test.txt
Delete line 15 of test.txt and all subsequent lines

Delete the line containing 'bash' in test.txt

Replace 'root' in test.txt with 'ha'

Replace '/sbin/nologin' in test.txt with '/bin/login'
Print odd lines in /etc/passwd?