MinMax Corp has the following capital structure: 55% equity (giving a return of9%), 10% preferred shares (with a yield of 6%), and 35% debt (with a coupon rate of 10% and yield to maturity of 6.5%). If corporate tax rate of 40%, what is the firm's WACC? a) 10.333% b) 9.050% c) 7.825% d) 6.915%