Numerous surveys have documented excessive drinking among college students. Suppose a random sample of 10 freshman students and a random sample of 15 senior students at Boylston University are selected to participate in a study. Each student in the sample is asked to record his/ her beer consumption throughout the year. At the end of the year, averages for the two samples are computed. Assume the average weekly beer consumption for the freshmen sample turned out to be 64.5 ounces, with a standard deviation 9.1 ounces, and that the average weekly consumption for the senior sample turned out to 32.4, with a standard deviation of 9.7 ounces. Build an 80% confidence interval estimate of the difference in average weekly beer consumption for the population of freshmen and the population of seniors at Boylston.