In 2018, the student body of a certain university consisted of 30% freshmen, 25% sophomores, 27% juniors, and 18% seniors. A sample of 400 students taken from the body of the students in 2019 showed that there are 138 freshmen, 88 sophomores, 94 juniors, and 80 seniors. The sample data are given in the table below. Freshmen Sophomores Juniors Seniors Observed frequencies 138 88 94 80 Expected frequencies State and test an appropriate hypothesis to determine whether the proportions of freshmen, sophomores, juniors, and seniors in the student body in 2019 are not the same as they were in 2018. Use 5% significance level. a. Place expected frequencies into the table. (1 mark) b. State null and alternative hypotheses. (1 mark) H: c. State the calculated value of test statistic. (1 mark) Xohs. = d. State the critical value of the test. (1 mark) XO. = e. Decide whether null hypothesis is true and make the conclusion whether the proportions of the students of different kind in 2019 are not the same as they were in 2018. (1 mark)