The Phillips Curve is steeper at higher rates of inflation and lower levels of unemployment

Why is a rightward shift of the labor supply curve difficult to rationalize in the classical model?

a. The labor supply curve is based on firms' preferences. b. Labor supply is very difficult to measure. c. The labor supply curve is almost never a known entity. d. Workers' preferences and therefore labor supply tend to change very slowly. e. Workers' preferences and therefore labor supply tend to change very quickly.

The Phillips Curve will shift when

A. the expected inflation rate changes. B. the overall employment rate remains unchanged. C. the price level falls. D. none of these.