When the market demand increases in a perfect competition, the long-run result is a larger number of firms, a higher price, and a permanent economic profit for the firms

The scientific evidence on the causes and consequences of global warming

a. is clear and indisputable. b. has considerable uncertainty in its findings. c. indicates global warming should be stopped regardless of cost. d. is of no importance to economists.

The demand curve for labor slopes down because

A. firms must lower prices to sell the additional units of its product that the extra workers produce. B. of the law of diminishing marginal product. C. firms value less efficient workers less than they value more efficient workers. D. of profit maximizing behavior.