Jennifer deposits 1000 into a bank account. The bank credits interest at a nominal annual rate of i convertible semiannually for the first 9 years and at a nominal annual rate of 2i convertible quarterly for all years thereafter. The accumulated amount in the account at the end of 6 years is X. The accumulated amount in the account at the end of 13.5 years is 1750. Calculate X. [1.a(vi-ix) #06]