I need help with these questions in the Linux system!

19: In your /home directory modify the .bash_profile file so that when you login you are greeted with "Last Day of Class" appearing on the screen. 20: In your /home directory, create a new empty directory named test3. Change the permissions on test3 so that the owner has rwx, your primary group as r-x, and all users have r only permissions. Move into this directory. All work from this point forward should be done in this directory unless stated. 21: Create new blank files named elephant, manatee, and ostrich. Write a script named script 21.sh that deletes elephant and zebra. (No, zebra does not exist, that's the point). Run the script with standard error redirected to a file named error21.out. 22: Write a script named script22.sh that asks the user to enter a username into a variable, then plugs that username into the command ps -ef | grep username > > question22.out. Run this script. 23: Write a script named script23.sh that asks the user what file they'd like to pull data from. Accept the filename as input. Ask the user to input what delimiter to use. Accept a character as input. Use the cut command to pull the second field out of the file with the delimiter given by the user and dump this information to a file named question23.out. 24: Copy the /tmp/testpass file into this test3 directory using the same filename. Look at the file and see what character is used as a delimiter. Run script23.sh, using testpass as the filename and the correct delimiter