If the market in the figure above changes from perfectly competitive to a profit-maximizing single-price monopoly, the amount of the gain in producer surplus is the area ________

Refer to the graph below, which shows the market for beef where demand shifted from D1 and D2. The change in equilibrium from E1 to E2 is most likely to result from:

A. A decrease in consumer incomes
B. An increase in the cost of cattle feed
C. An increase in the price of pork
D. A decrease in the tax on beef products

Suppose you are planning to sell your house. You value your house at $200,000. If you do not hire a realtor, you will be able to sell your house to a buyer whose reservation price is $220,000. If you hire a realtor, you will be able to sell your house to a buyer whose reservation price is $250,000. Assume that the realtor's opportunity cost of negotiating the sale is $5,000. In this case, how much additional economic surplus is generated by using a realtor to sell your house?

A. $25,000. B. None, because you value the house at $200,000 no matter who buys it. C. $200,000. D. $250,000.