Solve the following macroeconomic model wherein;
Y = C + I + G + NX is the equilibrium condition in macroeconomic model
C = 1500 + 0.75Y consumption function ( C = C0+cYd), where c is MPC
I = 1250 planned investment function
G =1250 government purchases function
NX = - 250 net export function
a. Find the value of Real GDP (Y) by solving above macroeconomic model? b. If the value of Marginal Propensity to Consume (MPC) increases from c =0.75 to c = 0.80, then how it will affect the Real GDP (Y) in the economy?