E6-4B (Computation of Future Values and Present Values) Using the appropriate interest table, answer the following questions. (Each case is independent of the others). (a) What is the future value of 20 periodic payments of $12,000 each made at the beginning of each period and compounded at 6%? (b) What is the present value of $7,500 to be received at the beginning of each of 30 periods, discounted at 8% compound interest? (c) What is the future value of 15 deposits of $6,000 each made at the beginning of each period and compounded at 8%? (Future value as of the end of the fifteenth period.) (d) What is the present value of six receipts of $3,000 each received at the beginning of each period, discounted at 10% compounded interest