A firm has 6,200 bonds outstanding with a face value of $1,000 per bond. The bonds carry a 6 percent coupon, pay interest semiannually, and mature in 6 years. The bonds are selling at 84 percent of face value. The company's tax rate is 34 percent. What is the firm's after-tax cost of debt? O3.82 percent O 4.78 percent 05.28 percent O 6.31 percent 9.57 percent