Based on the amounts of taxable income provided, compute the federal income tax payable in 2018 on each amount assuming the taxpayers are married filing a joint return. Also, for each amount of taxable income, compute the average tax rate and the marginal tax rate.

a. taxable income of $72,000

b. taxable income of $90,000

c. taxable income of $380,000

d. taxable income of $690,000

This is all the information that was given.