An annuity has end of quarter payments for fifteen years, and the payment at the end of the j-th quarter (j = 1, 2, ..., 60) is $100j. The payments are made directly into a savings account with a nominal interest rate of 7% payable monthly, and they are left in the account. (a) Find the effective interest rate for a quarter, and use the exact value to compute the balance in the savings account immediately after the last payment. (Round your answer for the interest rate to two decimal places. Round your answer for the balance to the nearest cent.) Answer: Effective interest rate for one quarter is (Round your answer to five decimal places) b) Balance after last payment is $ (Round your answer to the nearest cent.)