You can invest in taxable bonds that are paying a yield of 8.7 percent or a municipal bond paying a yield of 7.25 percent. Assume your marginal tax rate is 21 percent. a. Calculate the after-tax rate of return on the taxable bond? (Round your answer to 2 decimal places. (e.g., 32.16) b. Which security bond should you buy? a. Rate of return b. The security bond one should buy is