please answer as fast as possible !?

21. Sauer Milk, Inc., wants to determine the minimum cost of capital point for the firm. Assume it is considering the following financial plans: Cost (aftertax) Weights 5.09 10.0 20% 10 70 14.0 5.5% 10.5 15.0 30% 10 60 Plan A Debt Preferred stock Common equity Plan B Debt Preferred stock Common equity Planc Debt Preferred stock Common equity Plan D Debt Preferred stock Common equity 6.09 10.7 15.8 40% 10 50 8.0% 11.2 17.5 50% 10 40 4. Which of the four plans has the lowest weighted average cost of capital? (Round to two places to the right of decimal point.) b. Briefly discuss the results from Plan C and Plan D, and why one is better than the other