Are college students who take a freshman orientation course more or less likely to stay in college than those who do not take such a course? The article "A Longitudinal Study of the Retention and Academic Performance of Participants in Freshmen Orientation Courses" (Journal of College Student Development [1994]: 444-449) reported that 50 of 94 randomly selected students who did not participate in an orientation course returned for a second year. Of 94 randomly selected students who did take the orientation course, 56 returned for a second year. Construct a 95% confidence interval for p1 - p2, the difference in the proportion returning for students who do not take an orientation course and those who do. Give an interpretation of this interval.