1. George & Martha Washington are married and file a joint income tax return. In 2016 the couple had $ 250,000 of total income and $ 200,000 in taxable income. a. Calculate the Washingtons 2016 federal income tax liability (tax rate schedule is in appendix D in your book). b. What is the Washingtons marginal federal tax rate for 2016? c. What is the Washingtons average tax rate for 2016? d. What is the Washingtons effective tax rate for 2016? e. The Washingtons are expecting an additional $ 20,000 in income. Which of the above rates is relevant to them concerning the additional income? Why?