A firm operating in a perfectly competitive market earns zero economic profit in the long run but remains in business because the firm's revenues cover the business owners' opportunity costs

Suppose you pre-ordered a non-refundable movie ticket to Avengers: Infinity War. On the day of the movie you decide that you would rather not go to the movie. According to economists, what is the rational thing to do?

A) Since you do not want to go to the movie and the cost of the movie ticket is a sunk cost, how much you paid for the ticket should not influence your decision. B) You should not waste resources. Since you have paid for the ticket you should watch the movie. C) Your should go to the movie to minimize your losses. D) You should go to the movie to maximize your utility.

The figure below illustrates the market for British pounds. D£ and S£ are the nonofficial demand and supply curves of the British pounds, respectively.A downward movement along the vertical axis would correspond to a(n) ________ of the U.S. dollar.

A. arbitrage B. appreciation C. swap D. depreciation