Please look up Australias resident tax rates for 2019-20 available on the Australian Taxation Office website. You will find a table containing 5 tax rates depending on income. Please use the rates contained in the table to answer the following questions. (a) For someone earning AU$30,000 of taxable income, what is her marginal and average tax rate? (b) For someone earning AU$150,000 of taxable income, what is her marginal and average tax rate? (c) For someone earning AU$1,000,000 of taxable income, what is her marginal and average tax rate? (d) What would have to be true about the taxable income of an Australian for her marginal and average tax rates to be the same? (e) Is the Australian income tax system progressive, flat, or regressive? Is that true at every taxable-income level?