A Company has two issues of debt. Issue A has a maturity value of 6 million dollars, a coupon rate of 8.00% paid annually, and is selling at par. Issue B was issued as a subordinate, 15 year bond 5 years ao. Issue B's coupon rate is 8.25%, paid annually. Risk has increased, and investors now demand a pre-tax return of 8.50% on issue B bonds. The maturity value of issue B is 4.5 million dollars. The firm has a marginal tax rate of 35%. What is the company's after tax cost of debt?

0.0821

0.0536

0.0527

0.0534

Please show your work.