Do students reduce study time in classes where they achieve ahigher midterm score? In a Journal of Economic Education article(Winter 2005), Gregory Krohn and Catherine O’Connor studied studenteffort and performance in a class over a semester. In anintermediate macroeconomics course, they found that “studentsrespond to higher midterm scores by reducing the number of hoursthey subsequently allocate to studying for the course.” Supposethat a random sample of n = 8 students who performed well on themidterm exam was taken and weekly study times before and after theexam were compared. The resulting data are given in Table 10.6.Assume that the population of all possible paired differences isnormally distributed. Table 10.6 Weekly Study Time Data forStudents Who Perform Well on the MidTerm Students 1 2 3 4 5 6 7 8Before 16 13 11 17 17 13 15 17 After 8 8 12 9 5 10 7 8 PairedT-Test and CI: Study Before, Study After Paired T for Study Before- Study After N Mean StDev SE Mean StudyBefore 8 14.8750 2.2952.8115 StudyAfter 8 8.3750 2.0659 .7304 Difference 8 6.50000 4.035561.42678 95% CI for mean difference: (3.12619, 9.87381) T-Test ofmean difference = 0 (vs not = 0): T-Value = 4.56, P-Value = .0026(a) Set up the null and alternative hypotheses to test whetherthere is a difference in the true mean study time before and afterthe midterm exam. H0: µd = versus Ha: µd ≠ (b) Above we present theMINITAB output for the paired differences test. Use the output andcritical values to test the hypotheses at the .10, .05, and .01level of significance. Has the true mean study time changed? (Roundyour answer to 2 decimal places.) t = We have evidence. (c) Use thep-value to test the hypotheses at the .10, .05, and .01 level ofsignificance. How much evidence is there against the nullhypothesis? There is against the null hypothesis.