1. State the expression for the change in the debt to GDP ratio (without money). a. Define the variables and explain what the expression means. b. Show what happens to the debt to GDP ratio if interest rates are greater than real GDP growth rates. c. Show what happens to the debt to GDP ratio if interest rates are less than real GDP growth rates. d. If an economy is in the situation stated in b., and the debt ratio is positive, how can the economy stabilize the debt? What are the possible consequences of doing so