Can you please help me with these questions,

Thank You very much

Advance, Inc., is trying to determine its cost of debt. The firm has a debt issue outstanding with 10 years to maturity that is quoted at 105 percent of face value. The issue makes semiannual payments and has a coupon rate of 10 percent annually. Required: (a) What is Advance's pretax cost of debt? (Do not include the percent sign Round your answer to 2 decimal places. (e.g., 32.16) Pretax cost of debt (b) If the tax rate is 35 percent, what is the aftertax cost of debt? (Do not include the percent sign Round your answer to 2 decimal places. (e.g., 32.16) Aftertax cost of debt