Compute global technology weighted average cost of capital

Question

Problem:

Global Technology's capital structure is as follows:

Debt
35%
Preferred stock
15%
Common equity
50%

The after-tax cost of debt is 6.5 percent; the cost of preferred stock is 10 percent; and the cost of common equity (in the form of retained earnings) is 13.5 percent.

Calculate Global Technology's weighted average cost of capital ( WACC ).