(weighted average cost of capital) the target capital structurefor QM industries

(weighted average cost of capital) the target capital structurefor QM industries is 37% common stock 15% preffered stock nd 48%debt. if the cost of common equity for the firm is 18.8% the costof preffered stock is 10.4% the before tax cost of debt is 7.9%and the firms tax rate is 35% whay is QMs weighted average cost ofcapital?