Use the aggregate supply-aggregate demand model to analyze the effects of a decrease in stock prices on the following. Assume the economy begins at full employment. Please express all effects (increase, decrease, no change) relative to the initial position. Please include a well-annotated graphical analysis.

a. Real output in the short run[ increase, decrease, no change ]

b. Price level in the short run[ increase, decrease, no change ]

c. Real output in the long run[ increase, decrease, no change ]

d. Price level in the long run[ increase, decrease, no change ]