The firm$$s capital structure includes $30\%$ debt and $70\%$ of equity. The required rate of return of bondholders is $6\%,$ Assume that the expected dividend $($D$1)$ on each share of common stock is $$2.$ Each share of common stock is currently trading at $$40$ and has an expected growth rate of $5\%.$ The firm$$s tax rate is $25\%.$ Calculate the weighted average cost of capital.