1.A firm purchased copper pipes a few years ago at $10 per pipe and stored them, using them only as the need arises. The firm could sell its remaining pipes in the market at the current price of $9. What is the opportunity cost of each remaining pipe and what is the sunk cost?

2.Assume that the fixed costs for a soybean farm, which include the costs of land, equipment and fertilizer is $10,000 per year and that labor is the only variable cost of running the farm. And assume that the firm pays each worker $2,000 a month. The productivity of labor is shown in the following table.