In 2019, Melinda is employed at a local university and has wages of $55,000. Melinda also has a Schedule C business where she plays piano and sings at social events. She has net income from the Schedule C of $18,000.

1. What is Melindas self-employment tax?

2. If Melindas income had been $150,000 from the university, what would her self-employment tax be?