The company's $102 preferred stock has been yielding 4 percent in the current market. Flotation costs for the company have been estimated by its investment banker to be $3.00 for preferred stock. The company's optimum capital structure is 40 percent debt, 20 percent preferred stock, and 40 percent common equity in the form of retained earnings. Refer to the following table on bond issues for comparative yields on bonds of equal risk to Northwest. a. Compute the cost of debt, Kd. (Use the accompanying table-relate to the utility bond credit rating for yield.) Note: Do not round intermediate calculations. Input your answer as a percent rounded to 2 decimal places. b. Compute the cost of preferred stock, Kp. Note: Do not round intermediate calculations. Input your answer as a percent rounded to 2 decimal places. c. Compute the cost of common equity in the form of retained earnings, Ke. Note: Do not round intermediate calculations. Input your answer as a percent rounded to 2 decimal places. d. Calculate the weighted cost of each source of capital and the weighted average cost of capital. Note: Do not round intermediate calculations. Input your answers as a percent rounded to 2 decimal places