Consider the simple macro model

c=200+Yd

I=150

G=90

T=0.2Y

NX=60-0.2Y

a) Calculate the AE equation

b) Calculate the equilibrium level of Y, C, NX and T

C) What is public savings and private savings at equilibrium Y

D)What is MPC and the Multiplier

E)Calculate the change in Y if government spending rises by 20

f) If Y=1000, calculate the average propensity to save and average propensity to consume