Find the overall pre-tax and after-tax cost of debt for a company with the following bonds. The tax rate is 35%.:
a. Price of 1030, book value of $40 million, pre-tax cost of 6.5%
b. Price of 1080, book value of $35 million, pre-tax cost of 7.5%
c. Price of 970, book value of $55 million, pre-tax cost of 8.5%
d. Price of 1110, book value of $50 million, pre-tax cost of 9.5%