An Economy Has Government Purchases of 1000

An economy has government purchases of 1000.Desired national saving and desired investment are given by S^d = 200 + 5000r + 0.10Y - 0.20G
I^d = 1000 - 4000r
When the full-employment level of output equals 5000,then the real interest rate that clears the goods market will be

A) 1) 11%.
B) 5) 56%.
C) 16.67%.
D) 21.11%.