The math department at a community college wants to estimate math class sizes. They collect a random sample of classes and record the class size of each to obtain the following: 20, 20, 28, 26, 30, 21, 21, 18, 15, 28, 26, 28, 34, 24, 14, 28. A) What is the mean class size? B) What is the median class size? C) What is the mode of the class size?