the simple quantity theory of money, what will happen to Real GDP and price level as the money supply rises? Why?

In monetarism, how will each of the following affect the price level in the short run?
1. an increase in velocity
2. a decrease in velocity
3. an increase in the money supply
4. a decrease in the money supply



I wrote:

With an increase in money supply price level will increase.

does GDP stay the same? I'm not sure

1.?
2.?
3. Price level will increase because money supply increase
4. Price level with decrease because money supply decrease.