Sorensen System Inc. is expected to pay a dividend of $2.40 at year end, the dividend is expected to grow at a constant rate of 5.50% a year, and the common stock currently sells for $37.50 a share. The before-tax costs of debt is 7.50%, and the tax rate is 40%. the target capital structure consists of 45% debt and 55% common equity. what is the companys WACC if all the equity used is from retained earnings?