Find equilibrium GDP using the following macroeconomic model (the numbers, with the exception of the MPC, represent billions of dollars):
C = 500 +0.75Y
1=2,000
G = 1,250 I
NX = -100
Y = C+1+G+NX
Consumption function
Planned investment function
Government spending function
Net export function
Equilibrium condition
The equilibrium level of GDP is $ billion. (Round your answer to the nearest billion dollars.)