Sam deposits 500 into a fund today and 2000 fifteen years later. Interest is credited at a nominal discount rate of d compounded quarterly for the first 10 years, and at a nominal interest rate of 6% compounded semi annually thereafter. The accumulated balance is a fund at the end of 30 years is a thought. Calculate d.

11.93%

11.63%

11.83%

11.13%

11.33%

NOTE: I did this problem myself and got 11.63%, which is wrong. Therefore, is not the answer.