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Chuck, a single taxpayer, earns $76,000 in taxable income and $11,100 in interest from an investment in City of Heflin bonds. (Use the U.S. tax rate schedule) Required: a. If Chuck earns an additional $40,000 of taxable income, what is his marginal tax rate on this income? b. What is his marginal rate if, instead, he had $40,000 of additional deductions? Note: For all requirements, do not round intermediate calculations. Round percentage answers to 2 decimal places. Answer is complete but not entirely correct. a. Marginal tax rate 21.89 % b. Marginal tax rate 22.10 %