A study was conducted to see whether monetary incentives to use less water during times of drought had an effect on water usage. Sixty single family homeowners were randomly assigned to one of two groups: 1) monetary incentives and 2) no monetary incentives. At the end of three months, the total amount of water usage for each household, in gallons, was measured.
(a) What would be the appropriate hypothesis test to use to test the claim that monetary incentives reduce water usage?
(b) Why would you use this appropriate hypothesis?