Four different income tax decreases have been proposed by Congress. You want to know whether these plans will differ in their impact on people’s taxes. You randomly select 20 households and review...

Four different income tax decreases have been proposed by Congress. You want to know whether these plans will differ in their impact on people’s taxes. You randomly select 20 households and review each one’s 2007 tax records, then work out their savings under each of the four plans. (For each of the 20 households, you will have four savings calculations.) You want to compare the plans to see how they tend to differ.