6. Consider the investment problem in Exercise 8, Section 11. (a) Suppose the rate of return on the electronics stock increases to 5.2%. what is the optimal investment policy? (b) Suppose the rate of return on the utility stock decreases to 7%, what is the optimal investment policy? (c) Suppose the amount invested in the bond is at least $90,000. What is the optimal investment policy? 8. Investment problem. The administrator of a $200,000 trust fund set up by Mr Smith's will must adhere to certain guidelines. The total amount of $200,000 need not be fully invested at any one time. The money may be invested in three different types of securities: a utilities stock paying a 9% dividend, an electron- ics stock paying a 4% dividend, and a bond paying 5% interest. Suppose that the amount invested in the stocks cannot be more than half the total amount invested; the mount invested in the utilities stock cannot exceed $40,000; and the amount invested in the bond must be at least $70,000. What investment policy should be pursued to maximize the return