Final answer:
Shauna will be required to pay a total tax of $25,000 (25% of $100,000) on her distribution.
Step-by-step explanation:
To calculate the total amount of tax and penalty Shauna will be required to pay on her $100,000 distribution from her 401(k) account, you need to determine her tax liability based on her marginal tax rate of 25%.
Since Shauna received the distribution on her 59th birthday and she has not yet retired, she will not be subject to the early withdrawal penalty of 10%.
Therefore, Shauna will be required to pay a total tax of $25,000 (25% of $100,000) on her distribution.