Validate radio button

I created a form with 5 diferent departments, first user who will filled the form must choose 3 department and after that cick on button to send email for the first choosen department.

My question is: How can I insered an email address in each radio button and put this info in my email code, so the button can be able to send to the first choice, and second and third...I din´t know if I make myself clear.