18. Which of the following statements is CORRECT? a. Since debt capital can cause a company to go bankrupt but equity capital cannot, debt is riskier than equity, and thus the after-tax cost of debt is always greater than the cost of equity. b. The tax-adjusted cost of debt is always greater than the interest rate on debt, provided the company does in fact pay taxes. c. If a company assigns the same cost of capital to all of its projects regardless of each project