4. Given the following consumer choice problem. U(X1, X2) = X1 X2 s.t. P1 X1 + P2 X2= 150 L=X1 X2 0.3 07 + { x 150-P1 X1 -P2*2) max & OL =0.3X X2 - Ap1=0 OL =0.7X X2 d x2 -0.3 - Ap2=0 a x OL =150-P1X1-P2*2=0 . . . 150- p, *1 = P2 3*1pz . . . X- = 45 P1 equation 5 a) Explain the economic meaning of equation 5. (10 points) b) Write the expression for the marginal utility of good 2. (5 points)