suppose in Fiscalville there is no tax on the first 10000 of income but a 20 % tax on earning between $10000 and $20000 and a 30% tax on earnings between 20000 and 30000. any income above $30000 is taxed at 40%. if your income is $50000 how much will you pay in taxes? determine your marginal and average tax rates. is this a progressive tax? explain.