Answer:
Economists who view the AS curve as upward-sloping believe that changes on the demand side CAN result in changes in Real GDP in the short run. Economists who view the AS curve as vertical believe that government changes from the demand side CANNOT DO ANYTHING to raise Real GDP in the short run.
Step-by-step explanation:
In the short run, the aggregate supply (AS) curve is upward sloping because most input prices are fixed in the short run. So a change in the aggregate demand will cause the AS curve to change in the short run. If the demand increases, the aggregate supply will increase, and vice versa.
On the long run, input prices are not fixed, so the AS curve is vertical and any changes in the aggregate demand will not affect it.