A corporation can cam 7.5% if it invests in municipal bonds. The corporation can also carn 8.40% (before-tex) by investing in preferred stock. Assume that the two investments have equal risk. What is the break-even corporate tax rate that makes the corporation indifferent between the two investments? Assume a 10% dividend exclusion for tax on dividends. (Do not found you intermediate answer and round your final answer to two decimal places.) O.43.93% b.27.50% OL 32 50% d. 35.71% O. 28.57%