Can anyone help me figure out a formula for the following sliding bonus
scenario:

To receive a bonus, Gross Profit must be at least $250,000
Once minimum is met, bonuses are calculated as a percent of the Adjusted GP
(GP minus $250,000) as follows:

If Actual GP is under $500,000:
3% of Adjusted GP

If Actual GP is $500,000 up to $750,000:
3% of first $250,000
4% of balance of Adjusted GP

If Actual GP is over $750,000:
3% of first $250,000
4% of second $250,000
4.5% of balance of Adjusted GP

Thanks!!