A business student argues that an MBA student is required to prepare more than five cases per week. A statistics professor decides to evaluate the claim using a random sample of MBA students. Each student report the number of cases they prepare weekly: {2, 7, 4, 8, 9, 5, 11, 3, 7, 4}.
(a) Write the null hypothesis and alternative hypothesis.
(b) Assuming that the number of cases is normally distributed with a standard deviation is 1.5, can we conclude at 5% significance level that the claim is true?