Which of the following statements is CORRECT?

• Since the money is readily available, the cost of equity using retained earnings is usually much lower than the after-tax cost of debt.
• If a companys tax rate increases but the YTM on its non-callable bonds remains the same, the after-tax cost of its debt will fall.
• All else equal, an increase in a companys stock price will increase its marginal cost of retained earnings, r_s.
• When calculating the cost of preferred stock, a company needs to adjust for taxes, because preferred stock dividends are deductible by the paying corporation.
• All else equal, an increase in a companys stock price will increase its marginal cost of new common equity, r_e.