= Sorensen Systems Inc. is expected to pay a $3.60 dividend at year end (D1 = $3.60), the dividend is expected to grow at a constant rate of 4.00% a year, and the common stock currently sells for $57.50 a share. The before-tax cost of debt is 5.50%, and the tax rate is 25%. The target capital structure consists of 45% debt and 55% common equity. What is the company's WACC if all the equity used is from retained earnings? Do not round your intermediate calculations. a. 6.89% b. 7.19% c. 6.09% d. 7.64% e. 7.50%