A command economic system does not need to be concerned with what to produce, how to produce things, or who will get the goods and services produced

If the production of a good causes an external cost, then the efficient quantity is

A) equal to the quantity at which the marginal benefit equals marginal cost. B) less than the quantity at which the marginal benefit equals the marginal cost. C) more than the quantity at which the marginal benefit equals the marginal cost. D) the quantity at which the marginal private benefit is greater than the marginal social benefit. E) None of the above answers is correct.

In the short run, a negative supply shock

a. causes firms' unit costs to decrease b. shifts the AS curve to the right c. causes output to decrease and the price level to increase d. shifts the AD curve to the left e. causes both output and the price level to decrease