Two high schools have a similar number of students and parking lots of similar size. The safety officers at both schools want to investigate whether there is an average difference in the number of cars parked per day in the student parking lots for the school year. A random sample of 15 school days will be selected. For each selected day, the number of cars parked in the student parking lots will be counted at both schools and the difference will be recorded. Assuming all conditions for inference are met, which of the following is the appropriate test for the investigation? a. A two-sample 2-test for a difference between proportions
b. A two-sample t-test for a difference between means
c. A matched-pairs t-test for a mean difference
d. A chi-square test of homogeneity
e. A chi-square test of independence