Need help with shell scripting and using the sed command in Linux/Unix

Consider the address book below:

$ cat addr

Xiao Li, lxiao@unc.edu, 6705462234, Jackson, NC 764

Elizi Moe, emoe@ncsu.edu, 5208534566, Tempe, AZ 85282

Ma Ta, mta@yahoo.com, 4345667345, Austin, TX 91030

Diana Cheng, dcheng@asu.edu, 5203456789, Matitsi, WY 4587

Jackson Five, jfive@ncsu.edu, 5206564573, Kyenta, AZ 85483

Adi Srikanth Reddy, sadi1@imap1.asu.edu, 6578904566, Wyo, WS 67854

Natkin William, wnatkin@imap28.asu.edu, 8044344528, Richmond, VA 22345

Provide the sed command to:

Substitute the 3rd occurrence of asu in email address with vcu.

Remove all imap and imap number from the email addresses

Add the string School Email next to all email addresses ending with .edu

Move the email addresses to the end of the lines