Suppose Hellca Co. has the following information, what is its after-tax cost of debt if it has a WACC of 12.9%? It has a 40% corporate tax rate and is funded as follows. $35,000,000 equity with a return of 17% $21,000,000 debt $14,000,000 preferred with a 13% cost of preferred a) 12% b) 8% O c) 10% d) 6%