Much of the Empirical Evidence on the Behavior of Costs

Multiple Choice

Much of the empirical evidence on the behavior of costs for real-world firms suggests that:

A) average costs functions are U-shaped as suggested by economic theory.
B) for most firms, marginal costs are declining in the range in which the firms operate.
C) for many firms, marginal and average variable costs are constant over wide ranges of output.
D) there is no relationship between the marginal and average variable costs of production.