Consider the following simple Keynesian macroeconomic model for a closed economy, consisting of 4 equations in 4 unknowns (endogenous variables), namely A (Aggregate expenditure), C (Consumption expenditure), Ya (Disposable Income) and Y (Income). Simple Keynesian Macroeconomic Model 1) A = C+I+G 2) C =a+bYa 3) YO = Y-T 4) Y = A 7Furthermore, the values of the exogenous variables and the MPC (marginal propensity to consume) are given below. Note that tax is not considered to be an income tax, it is assumed to be a lump-sum autonomous tax totally independent of income. a = R100 million (autonomous consumption) b = 0.8 (marginal propensity to consume) I = R300 million (investment expenditure) G = R180 million (government expenditure) T = R100 million (autonomous tax) (a) Calculate the equilibrium level of income (Y). Show all workings. (5 marks) (b) Calculate the equilibrium level of consumption (C). Show all workings. (5 marks) (c) Is the government running a budget deficit or a budget surplus? Give reasons for your answer. (2 marks) (d) What is the value of the multiplier? Show all workings. (3 marks) (e) Assume that the full employment level of income is equal to R3000 million. By how much should the government increase its expenditure to achieve full employment? Show all workings