Two goods are substitutes when a decrease in the price of one good

The U.S. experience during the 1980s and 1990s illustrates that

a. fiscal policy is substantially more potent than monetary policy. b. a balanced budget is essential for the achievement of price stability. c. a monetary policy that keeps the inflation rate low and steady will help promote economic stability. d. there is a trade-off between inflation and unemployment-the unemployment rate can be reduced if we are willing to tolerate higher rates of inflation.

Which of the following statements regarding the relationship between average and marginal costs is INCORRECT?

A) There is always a definite relationship between average and marginal cost. B) When marginal costs are less than average costs, the latter must fall. C) When marginal costs are greater than average costs, the latter must rise. D) There is no way for average variable costs to fall when marginal costs are falling.