Explain the effect, if any, that each of the following occurrences should have on the aggregate demand curve.

a. The Fed lowers the discount rate.

b. The price level decreases.

c. The federal government increases federal income tax rates in an effort to reduce the federal deficit.

d. Pessimistic firms decrease investment spending.

e. The inflation rate falls by 3 percent.

f. The federal government increases purchases to stimulate the economy.