单选题 Last school year, the student body of a local university consisted of 30% freshmen, 24% sophomores, 26% juniors, and 20% seniors. A sample of 300 students taken from this year's student body showed the following number of students in each classification.Freshmen 83Sophomores 68Juniors 85Seniors 64We are interested in determining whether or not there has been a significant change in the classifications between the last school year and this school year. The expected number of freshmen is