Scot and Vidia, married taxpayers, earn $240,000 in taxable income and $5,000 in interest from an investment in City of Tampa bonds. (Use the U.S. tax rate schedule for married filing jointly). Required: a. If Scot and Vidia earn an additional $80,000 of taxable income, what is their marginal tax rate on this income? b. What is their marginal tax rate if, instead, they report an additional $80,000 in deductions? (For all requirements, round your answers to 2 decimal places.) a. Marginal tax rate b. Marginal tax rate % %