Answer:
c. 10% and 10%
Explanation:
The income tax rate are progressive, this means the rates applies for the amount above the top of the previous bracket
Sam will be taxes with a higher rate in the subsequent dollars and end up with the 39.6% tax for their last part of income
But, as state beore the tax is progressive not all gains are taxes wit hthe same tax-rate
Also is important to notice this makes both making equal contribution when they are equal (below a certain threshold) and then, being treated unequally when their income are different