QUESTION 9 Check all of the following that are true. the government generates zero tax revenue at both the zero percent tax rate and the 100 percent tax rate, as shown in the Laffer curve a certain level of taxes is necessary, but raising tax rates retards economic growth O some of the things Congress and the President need to consider when changing tax rates are inflation, automation, and "fairness" O the Smoot-Hawley Tariff Act raised import tax rates during the Great Depression but led to lower revenue from those tariffsQUESTION 24 In the market for cell phones, which of the following shifts the demand curve to the right? O An increase in the price of cell phones O A decrease in the price of cell phones O An increase in the price of land-line phone service O A decrease in the price of land-line phone service O A decrease in the number of cell phone buyers