A $100 Billion Decrease in Government Purchases in an Economy

A $100 billion decrease in government purchases in an economy, other things constant, would:

A) increase aggregate demand by approximately $500 billion if the marginal propensity to consume were 0.8
B) decrease aggregate demand by approximately $300 billion if the marginal propensity to consume were 2/3
C) increase aggregate demand by $ approximately 200 billion if the marginal propensity to consume were 0.5.
D) decrease aggregate demand by approximately $40 billion if the marginal propensity to consume were 0.4
E) increase aggregate demand by approximately $400 billion if the marginal propensity to consume were 0.4.