Marysa Corp. issued a 20-year, 6 percent semiannual bond 4 years ago. The bond currently sells for 91 percent of its face value. The companys tax rate is 23 percent. a. What is the pretax cost of debt? (Do not round intermediate calculations and enter your answer as a percent rounded to 2 decimal places, e.g., 32.16.) b. What is the aftertax cost of debt? (Do not round intermediate calculations and enter your answer as a percent rounded to 2 decimal places, e.g., 32.16.)