What is meant by a progressive tax? A regressive tax? A proportional tax? Comment on the progressivity or regressivity of each of the following taxes, indicating in each case where you think the tax incidence lies: ( a ) the Federal personal income tax; ( b ) a 4 percent state general sales tax; ( c ) a Federal excise tax on automobile tires; ( d ) a municipal property tax on real estate; ( e ) the Federal corporate income tax.