Help i’m not sure what to do, also if you answer this plsss explain how you got it :) !

Which expression converts 45 degree to radians

At the beginning of 1974/75,2 years a man invested #2000 in a bank at 12.5% compound interest, if it degree #650 at the end of each two years to pay his son's school fees, after payment of interest to pay his son's school fees, how much did he have left at the beginning of the 1978/79 school year?

Prove that 16^4-2^13-4^5 is divisible by 11.