weston corporation has some money to invest and its tresurer is choosing between general motors bonds and state of illinois bonds. both have the same maturity and they are equally risky and liquid. if the illinois bonds, which are tax exempt, yield 6 percent and westons marginal income tax rate is 40 percent what yield on GM bonds would make westons treaurer indifferent between the two

6.0

7.5

10.0

12.5

15.0