1. A company is interested in comparing the mean sales revenue per salesperson at two different locations. The manager takes a random sample of 10 salespeople from each location independently and records the sales revenue generated by each person during the last four weeks. He decides to use a t-test to compare the mean sales revenue at the two locations.

2. A team of engineers at the research center of a car manufacturer performs crash tests to determine the proportion of times the cars' airbags fail to operate in a crash. With the airbag system's new modified design, the team expected to reduce the failed proportion to be below last year's proportion of0.08. They decided to test H0: p = 0.08 versus Ha: p < 0.08, where p = the proportion of failed airbags during crash tests.

If 300 crashes performed in the lab resulted in 18 failures, which of the following is the test statistic for this test?