Mildred is a single person who is a 25 percent owner of a local business that operates using the name Four Rivers. The business reports $500,000 of taxable business income for the year 2020. Assume the business income allocated to Mildred is qualified business income. For each of the independent parts a) through d) below, show your calculation of the following four items and provide a brief explanation of how you determined each amount (i.e., why an amount was included or excluded from the calculation):

1. Mildreds self-employment tax liability (if any) related only to Four Rivers.
2. Mildreds additional Medicare tax liability (if any) related only to Four Rivers.
3. Mildreds qualified business income deduction (if any) related only to Four Rivers.
4. Mildreds net investment income tax liability (if any) related only to Four Rivers assume no investment expenses.

D) ) Assume Four Rivers is taxed as an S corporation, and Mildred works full-time for the business. In return, she receives a salary of $100,000 that was already taken into account when determining the partnerships $500,000 of taxable business income. Before considering her business income allocation from Four Rivers, and the self-employment tax deduction (if any), Mildreds adjusted gross income is $250,000, which includes the $100,000 salary from Four Rivers and $150,000 salary from working as an employee at an unrelated business.