equilibrium real GDP and the longrun equilibrium price level

Explain how, if at all, each of the following events would affect equilibrium real GDP and the longrun equilibrium price level.
a. A reduction in the quantity of money in circulation
b. An income tax rebate (the return of previously paid taxes) from the government to households,
which they can apply only to purchases of goods and services
c. A technological improvement
d. A decrease in the value of the home currency in terms of the currencies of other nations