A debt of $35,900 is repaid by payments of $2,980 made at the end of every six months. Interest is 10.62% compounded annually. (a) What is the number of payments needed to retire the debt? (b) What is the cost of the debt for the first four years? (c) What is the interest paid in the eighth payment period? (d) Construct a partial amortization schedule showing details of the first three payments, the last three payments, and totals. (a) The number of the semi-annual payments is (Round the final answer up to the nearest whole number. Round all intermediate values to six decimal places as needed.)