The calculation of WACC involives calculating the weighted average of the required rates of return on debt, preferred stock, and camman equity, ntiere the weights equal the percentage of each type of financing in the firm's overall capital structure. Is the symbol that represents the before-tax cost of debt in the weighted average cost of capital (Wacc) equation, Bryant Co. has $3.9 million of debt, $2 miltion of preferred stock, and $1.2 million of common equity. 0,55 0.25 0.17 0.22