14-23. Calculating the weighted average cost of capital) In the spring of last year, the man- agement of the Silver Steel Company learned that the firm would need to reevalu- ate the company's weighted average cost of capital following a significant issue of debt. The firm now has financed 40 percent of its assets using debt and 60 percent using equity. Calculate the firm's weighted average cost of capital where the firm's borrowing rate on debt is 6 percent, il faces a 40 percent tax rate, and the common stockholders require an 15 percent rate of return