If GDP is confidently expected to grow at a rapid 4% rate this year, how do you predict investment spending will change? Is it likely to grow faster than, slower than, or at the same rate as GDP? Why? Based on this expectation, investment spending is likely to by 4%. A rapidly growing economy will generally make business people optimistic, expectations about potential future profits. As a result, they are eager to invest.

Based on this expectation, investment spending is likely to increase by more than 4%.  

A rapidly growing economy will generally make business people more optimistic, with higher expectations about potential future profits. As a result, they are more eager to invest.

Investment will increase higher than 4% because in a growing economy like this, people will be so optimistic that they would invest huge sums to capitalize on the growth and earn some returns.

This rate of increase would be greater than GDP because GDP is based on multiple factors including investment therefore those factors like government spending would have to increase as well.