What Is the WACC for a Firm with 40% Debt

What is the WACC for a firm with 40% debt, 20% preferred stock and 40% equity if the respective costs for these components are 9.23% before-tax, 12% after-tax, and 18% before-tax? The firm's tax rate is 35%.

A) 9.48%
B) 11.16%
C) 12.00%
D) 15.60% WACC = (.4 x (1-35%) x .0923) + (.2 x .12) + (.4 x .18)
= ) 024 + .024 + .072