Answer each of the following questions. a. What single investment made today, earning 12% annual interest, will be worth $ 6,000 at the end of 6 years? b. What is the present value of $ 6,000 to be received at the end of 6 years if the discount rate is 12%? c. What is the most you would pay today for a promise to repay you $ 6,000 at the end of 6 years if your opportunity cost is 12%? d. Compare, contrast, and discuss your findings in parts a through c.