Studies show that smaller class sizes have a direct impact on student success. Researchers selected a random sample of 66 elementary school classrooms across the United States and found that the mean class size was 23 students with a standard deviation of 1 students. They also selected a random sample of 43 high school classrooms across the United States and found that the mean class size was 22.4 with a standard deviation of 2.5 students. (a) Construct a 95%