finance help

Weighted average cost of capital -- The target capital structure for QM industries is 42%  stock, 15% preferred stock, and 43%, debt. If the cost of common equity for the firm is 18.9%, the cost of preferred stocks 10.8%, the before tax cost of debt is 8.3%, and the firms tax rate is 35%, what is the QM's weighted average cost of capital?

QM's WACC is ____%