The City of Willford levies a flat 7% tax on individual income in excess of $55,000. Individuals who earn $55,000 or less pay no income tax.\ Ms. Vello earned $127,200 income this year. Mr. Sui earned $68,900 income this year. \ \ Please no dollar signs or percentage signs. For example, $5,000 should be entered as 5,000 (round to nearest dollar, no decimal points, USE commas if necessary!). For percentages, no signs and two decimal points, for example, 6.75% should be entered as 6.75. Not following these directions will result in zero credit, no exceptions.):\ \ What type of tax rate structure is the above representative of?