a. To calculate the company's pretax cost of debt, we need to use the embedded cost of debt. In this case, the embedded cost of debt is given as 5.2 percent annually. Since the debt issue makes semiannual payments, we need to divide the annual rate by 2 to get the semiannual rate.
Annual rate: 5.2%
Semiannual rate: 5.2% / 2 = 2.6%
Therefore, the company's pretax cost of debt is 2.6%.
b. To calculate the aftertax cost of debt, we need to consider the tax rate. In this case, the tax rate is given as 21 percent.
Aftertax cost of debt = Pretax cost of debt * (1 - Tax rate)
Aftertax cost of debt = 2.6% * (1 - 0.21) = 2.6% * 0.79
Therefore, the company's aftertax cost of debt is 2.054%.