Profit of one property can be settled against 2nd property

Hi,

      I have two properties....Property 1 is 100% owned by me and i am planning to sell that. Property 2 is co-borrowed and co-own by me/my wife/my father.

     Questions i have:

1. If i sell 1st property and profit that i get from that, can i pre-pay loan amount of 2nd property?

2. What is my income tax liablitiy from 1st home ( bough before 5 yrs)?

Thanks in advance.

Thanks

Kunal.