9 Question 12 (2.5 points) Which of the following conditions might cause the Aggregate Expenditure (AE) curve to shift upward (Think the graph where the vertical axis measures Aggregate Expenditure and horizontal axis measures real GDP): 1 12 A decrease in government expenditure 15 An increase in corporate Income taxes People are very optimistic about the future (expectation) 17 18 An increase in real interest rate