What is the appropriate statistical analysis to use: t-test for two independent samples, t-test for two dependent samples, ANOVA, or chi-square test

(a)  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.