Jack has taxable income of $65,000. He is a single tax filer, and his federal income tax rates on the first $8,350 is 10%; it is 15% on income from $8,350 to $33,950 and 25% on income from $33,950 up to $82,250. What is Jack's federal income tax liability, what is his marginal rate, and why would he care? Finally, what is his average federal tax rate? Show all of your work for full credit.