Final answer:
In the immediate market period, the vertical AS (Aggregate Supply) curve is vertical and represents a period when the price level is flexible, but the level of output is fixed.
Step-by-step explanation:
In the immediate market period, the vertical AS (Aggregate Supply) curve is vertical.
In the short run, the vertical AS curve represents a period when the price level is flexible, but the level of output is fixed. This means that any changes in the aggregate demand would only affect the price level and not the output.
For example, if there is an increase in aggregate demand, the price level will rise, but output will remain the same. Conversely, if there is a decrease in aggregate demand, the price level will decrease, but output will still be unchanged.