3. Many years ago, there were calls to simplify federal personal income tax code. One proposal was a flat tax. Under this proposal, each individual is allowed a standard deduction of, say, $20,000, and each family is allowed a standard deduction of $40,000. No other exemptions and deductions are allowed. The remaining income is subject to one flat tax rate of say, 20%. (2 Point) Please analyze the vertical equity of a flat tax designed like this, from both marginal tax rate and average tax rate perspectives. Is it a progressive, proportional, or regressive tax