R.S. Green has 250,000 shares of common stock outstanding at a market price of $28 a share. Next year's annual dividend is expected to be $1.55 a share. The dividend growth rate is 2 percent. The firm also has 7,500 bonds outstanding with a face value of $1,000 per bond. The bonds carry a 7 percent coupon, pay interest semiannually, and mature in 7.5 years. The bonds are selling at 98 percent of face value. The company's tax rate is 28 percent. What is the firm's weighted average cost of capital?