Given the following tax structure, what minimum tax would need to be assessed on Shameika to make

Question:

Given the following tax structure, what minimum tax would need to be assessed on Shameika to make the tax progressive with respect to average tax rates?
Taxpayer____ Salary ______Muni-Bond Interest _____ Total Tax
Mihwah ....... 10,000 .................10,000 ........................600
Shameika ...... 50,000 .................30,000 ........................???