If investment spending increases due to increased optimism in the business sector, which of the following would occur in the short-run? 0 an increase in GDP, an increase in the price level, an increase in money demand and an increase in the interest rate Q a decrease in GDP, a decrease in the price level, an increase in money demand and an increase in the interest rate Q a decrease in GDP, 3 decrease in the price level, a decrease in money demand and a decrease in the interest rate 0 an increase in GDP, 3 decrease in the price level, an increase in money demand and a decrease in the interest rate