Despite obtaining an extension to file his tax return, Raj Koothrappali filed his 2020 tax return late on December 22, 2021. His return showed taxable income of 88,000. His filing status is head of household.

1. Calculate his federal income tax liability.
2. He had federal taxes withheld during 2020 of $3,000. Identify what penalties he owes if any, and how much each penalty would be.

What is his marginal tax rate?

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