Walther Co. has a beta of .85. The market risk premium is 6.0% and the risk-free rate is 5.0%. The firm has a debt-to-equity ratio of .25 and a cost of debt of 9.0%. The applicable tax rate is 21%. a) What is the firms unlevered beta? b) What is the firms WACC? Now assume that the firm has a target debt-to-equity ratio of .50. c) What is the levered beta with the target D/E ratio? d) What is the WACC with the target D/E ratio?