Jean and Walter Pereira financed the addition of a swimming pool using a $24,000 home improvement loan from their bank. Monthly payments of $500 (except for a smaller final payment) include interest at 7.2% compounded semiannually. Construct a partial amortization schedule showing details of the first two payments, Payments 28 and 29, and the last two payments. What total interest will the Pereiras pay over the life of the loan?