Suppose that in a two-sector economy with only households and firms, consumption C =100 + 0.8Y, investment I = 150-6R, nominal money supply M=250, price level P=1, and money demand L= 0.2Y + 100-4R.

 (1) Calculate IS and LM curves;

(2) Calculate interest rate and income when product market and money market are in equilibrium simultaneously.