Solve using Excel and show your work:

R.S. Green has 250,000 shares of common stock outstanding, issued at $25, 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 current market price of a bond is $980. The company's tax rate is 34 percent. What is the firm's weighted average cost of capital?