Marty Martinson has determined that the amount of his taxable income that he will report on line 11b of his Form 1040 tax return for 2020 is $100,000. He asks for your help in calculating his total tax that he will report on line 16 in each of the following independent scenarios:

a) Show your calculation of the amount of total tax Marty will report on line 16 assuming that Marty is single with no dependents and has no items to report on Schedule 2.

b) Show your calculation of the amount of total tax Marty will report on line 16 assuming that Marty is single with no dependents and reports $4,500 in self-employment tax on line 4 of Schedule 2 related to a Schedule C activity.

c) Show your calculation of the amount of total tax Marty will report on line 16 assuming that Marty is not married. Marty provides over half the cost of maintaining a household for himself and his 10-year-old son, who he claims as a dependent. Marty has no items to report on Schedule 2.

d) Show your calculation of the amount of total tax Marty will report on line 16 assuming that Marty is married, but will use the married filing separately filing status. Marty provides over half the cost of maintaining a household for himself and his 18-year-old son, who he claims as a dependent. Marty has no items to report on Schedule 2.