Suppose that the firm's only variable input is labor. When 50 workers are used, the average product of labor is 50 and the marginal product of labor is 75. The wage rate is $80 and the total cost of the fixed input is $500.What is the marginal cost?

Corrective taxes are often difficult to implement because _____

a. those affected by the externality are often loathe to use political means to implement the tax b. those creating the externality threaten to shut down c. those who suffer from the externality refuse to talk about it d. the creator of an externality will use political means to try to prevent the tax

An external cost is:

A. the cost of a warehouse. B. a cost of production in some other market. C. the economic harm that a positive externality imposes on others. D. the economic harm that a negative externality imposes on others.