Your firm has a before-tax return of $2000 on an investment of $1100 and a marginal tax rate of 35%. The overall cost of capital is 9%. The firm currently uses 45% debt financing with an expected return of 6%. If it increases its use of debt to 55%, the expected return on the debt will be 7%. Calculate your firms WACC under the proposed capital structure. Round your answer to the nearest tenth of a percent..