Help with this question please. Thank you

J\&R Renovation, Inc., is trying to determine its cost of debt. The firm has a debt issue outstanding with 12 years to maturity that is quoted at 104 percent of face value. The issue makes semiannual payments and has a coupon rate of 4 percent annually. a. What is the company's 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. If the tax rate is 23 percent, 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.)