For each of the following situations, use an AD/AS model to describe what happens to price levels and output in the United States in the short run. In each case assume the economy starts in long- and short-run equilibrium, and describe the appropriate shifts in the AS or AD curves. instructions: You may select more than one answer. Click the box with a check mark for correct answers and click to empty the box for the wrong answers. a. A stock market crash reduces people's wealth.O Aggregate demand shifts to the left. O Aggregate demand shifts to the right. O Aggregate supply shifts to the left. O Aggregate supply shifts to the right O Output falls output rises. O The price level rises. O The price level falls. b. The spread of democracy around the world increases consumer confidence in the United States. O Aggregate demand shifts to the left. O Aggregate demand shifts to the right. O Aggregate supply shifts to the left. O Aggregate supply shifts to the right.O output falls. O Output rises. O The price level rises.O The price level falls.