(a) A debt of $24,000, which is due 8 years from now, is instead to be paid off by four payments: $8000 now, $4000 in 4 years, $5000 in 6 years, and a final payment at the end of 8 years. What would...

(a) A debt of $24,000, which is due 8 years from now, is instead to be paid off by four payments: $8000 now, $4000 in 4 years, $5000 in 6 years, and a final payment at the end of 8 years. What would this payment be if an interest rate of 4% compounded semiannually is assumed?