I only have one chance so please get it correct ..

You are analyzing the after-tax cost of debt for a firm. You know that the firm's 12-year maturity, 9.25 percent semiannual coupon bonds are selling at a price of $903.28. If these bonds are the only debt outstanding for the firm. What is the current YIM of the bonds? What is the after tax cost of debt for this firm if it has a marginal tax rate of 34 percent? What is the current YTM of the bonds and after-tax cost of debt for this firm if the bonds are selling at par