Bonnie and Mike are married taxpayers who file a joint income tax return. In 2023, they have combined salaries (boxes 1, 3, and 5 of the W-2) of $250,000, investment income (included in the AGI) of $80,000, and their AGI is $315,000. They have investment interest expense of $10,000. Calculate the Medicare contribution tax (Net Investment Income Tax) that they must pay.