The best example of a progressive tax in the united states is

The best example of a progressive tax in the United States is  Federal Personal Income Tax.

Explanation:

A progressive tax is a scheme to pay tax where tax rate changes based on the taxable amount. If the taxable amount high or got increased then the tax to be paid also will be high and will get increased. This system used that a person with a low-income rate can pay only low taxes compared to a person with a higher income rate.

The main goal of this framework is not to encourage high earners to earn more and not to discourage low-income earners to become the poor. The United States established this income-tax system in 1862. The Federal tax authority also provides a personal exception that includes deductions in the taxes for low-income people.

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