Im currently using vodafone 2g (mumbai circle) (prepaid) and i am thinking to convert into 3g. But i have some questions:1. Do I need to change the sim? I am a bit doubful as my sim is 4 years old.2. Right now I am using Rs.199 2GB internet pack (2G network). Will it get deactivated automatically when 3g will get activated?3. Is it possible to use 2g data packs on 3g sim?