Healthy Fish expects to spend $52,000 to raise the fish. （假设养鱼无风险，鱼不会死）Suppose that Healthy Fish can enter into a futures contract to sell the entire batch of fish for $60,000. The contract will cost $3,000. What is the opportunity cost of capital for this investment? Should Healthy Fish make the investment? If Healthy Fish cannot set up a futures contract, what is its opportunity cost of capital? Should it invest in this case? Assume that the current interest rate on AAA corporate bonds is 6.25%, and that the historical rate of return on the stock exchange is 10%.