A system calculates the amount of customs duty to be paid:
_ No duty is paid on goods value up to, and including, $2,000.
_ The next $8,000 is taxed at 10%.
_ The next $20,000 after that is taxed at 12%.
_ Any further amount after that is taxed at 17%.
To the nearest $, which of these groups of numbers fall into three DIFFERENT equivalence classes?