. Decide whether you would reject or fail to reject the null hypothesis in thefollowing situations:a. ???????? = 3.50, sD = 1.10, n = 12, = 0.05, two-tailed testb. 95% ???????? = (0.20, 1.85)c. t = 2.98, t* = -2.36, one-tailed test to the leftd. 90% CI = (-1.12, 4.36)7. Calculate difference scores for the following data:Time 1 Time 2 XD61 8375 8991 9883 9274 8082 8898 9882 7769 8876 7991 9170 808. You want to know if an employee's opinion about an organization is thesame as the opinion of that employee's boss. You collect data from 18employee-supervisor pairs and code the difference scores so that positivescores indicate that the employee has a higher opinion and negative scoresindicate that the boss has a higher opinion (meaning that difference scores of0 indicate no difference and complete agreement). You find that the meandifference score is ???????? = -3.15 with a standard deviation of sD = 1.97. Testthis hypothesis at the = 0.01 level.9. Construct confidence intervals from a mean of ???????? = 1.25, standard error of???????????? = 0.45, and df = 10 at the 90%, 95%, and 99% confidence level.Describe what happens as confidence changes and whether to reject H0.pg. 17210.A professor wants to see how much students learn over the course of asemester. A pre-test is given before the class begins to see what studentsknow ahead of time, and the same test is given at the end of the semester tosee what students know at the end. The data are below. Test for animprovement at the = 0.05 level. Did scores increase? How much didscores increase?Pretest Posttest XD90 8960 6695 9993 9195 10067 6489 9190 9594 9583 8975 8287 9282 8382 8588 9366 6990 9093 10086 9591 96