Chuck, a single taxpayer, earns $75,000 in taxable income and $10,000 in interest from an investment in City of Heflin bonds. (Use the US tax rate schedule.) Required: a. How much federal tax will he owe? b. What is his average tax rate? c. What is his effective tax rate? d. What is his current marginal tax rate? Complete this question by entering your answers in the tabs below. Required A Required B Required C Required D