Interest and Gambling

Dealing in interest

Q: You know banks pay you interest if you have account with them and if use credit card you also pay interest to a bank. So if you receive and give interest(riba) would you be in hellfire forever? Below words from Quran says forever. Trade is like usury, but Allah hath permitted trade and forbidden usury. Those who after receiving direction from their Lord, desist, shall be pardoned for the past; their case is for Allah (to judge); but those who repeat (the offence) are companions of the Fire: they will abide therein (for ever). [2:275]

I thought only thing will put you in hellfire forever is shirk.

Cash prize draw

Q: To encourage consumers to complete an online customer survey can I offer them entry into a cash prize draw. 5 lucky respondents will get R1000 each for example. Is this permissible?

Medical insurance

Q: I had a question about a friend who sells his medication called Hydrocodone pain killer. He gets it for free under his insurance and sells it to relatives and friends to be used for pain killer? What's the ruling on that? 

Linking one's bank account with someone else's account

Q: Is it permissible for me to link my bank account with my father's bank account at the same bank which contains interest but I am not withdrawing any money neither am I depositing money from his account but just linking it? My account is interest free and the money in my account is not being shared with his money but the "link" is still there.  Is this permissible?