Dana intends to invest $72,000 in either a Treasury bond or a corporate bond. The Treasury bond yields 5 percent before tax and the corporate bond yields 6 percent before tax. a-1. Assuming Dana's federal marginal rate is 24 percent and her marginal state rate is 5 percent, which of the two options should she choose? Assume that Dana itemizes deductions. Corporate bond O Treasury bond a-2. How much interest after-tax would Dana earn by investing in the corporate bond? (Do not round intermediate calculations and round your final answer to the nearest whole dollar amount.) Interest after-tax b-1. If she were to move to another state where her marginal state rate would be 10 percent, which of the two options should she choose? Assume that Dana itemizes deductions. O Corporate bond Treasury bond