A question about '3 PC 1 year' license and activations

Hello :)

 

My father has been using Norton Internet Security for the last 11 months. We found a great deal for NIS 2012 where we can get a '3 PC 1 Year' license for NIS 2012 from a trusted online shop. However, I am confused as to whether both he and I can use it on our separate computers. This wouldn't matter if we lived in the same house but we live in separate cities. Can someone clarify this?

 

Also, I have a question about activations. Does properly unistalling NIS from one PC mean that you will be able activate it on another PC or will you need to contact Support for it?