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2. Macroeconomic Model: 3 points. The following represents a closed economy Y = C+I+G C = a + b YD Y' = Y-T T =tY Whereby: Y=Income; I=Investment; G=Government Spending; C=Consumption; YD = Disposable Income; T = Taxes; and (a, b, t) are parameters. Now assume that I=150, G=200, a=20, b=0.6, t=0.2. (i) Derive the solution for Y. And compute the value for Y as well as the corresponding value of the government budget balance. Is the government budget surplus or deficit? (ii) What is the value of the multiplier? Then, use the multiplier to explain how much does the value of Y change when the value of G increases by 50. Now assume that, G=200, a=20, b=0.6, t=0.2, but the investment is endogenously given by the following equation: I =S 1 Whereby, S is the savings, and is given by the difference between the disposable income and the consumption: S= YD - C. (iii) Solve for the value of Y