Suppose a firm borrow $5,000, and the loan is to be repaid in 4 equal payments at the end of each of the next 4 years. The bank charges a 10% interest rate on the loan balance that is outstanding at the beginning of each year. The proportion in year 3 payment that represents the repayment of principal is:
a. 75.12%. b. 82.64%. c. 17.36%. d. 31.71%.