Which of the following statements is CORRECT? a. An increase in the risk-free rate will normally lower the marginal costs of both debt and equity financing. b. A change in a company's target capital structure cannot affect its WACC. c. Flotation costs associated with issuing new common stock normally reduce the WACC. d. WACC calculations should be based on the before-tax costs of all the individual capital components. e. If a company's tax rate increases, then, all else equal, its weighted average cost of capital will decline