The state of Montana levies an income tax with the following rate structure.Rate Income bracket5% $-0- to $50,00010% $50,001 to $150,00020% $150,001 and aboveA. Mrs. Smith's annual income is $120,000. Compute her tax, her average tax rate, and her marginal tax rate.B. Mr. Rose's annual income is $230,000. Compute his tax, his average tax rate, and his marginal tax rate.C. Does Montana have a proportionate, progressive, or regressive tax rate structure?