2. Another researcher was interested in the same question, but decided to conduct a longitudinal study, using a repeated-measures design. She used a sample of 16 students, measured their stress levels in their first year of college, and then measured their stress levels once again when they were in their second year. These were here results: Subject Stress level in first year Stress level in second year A 55 65 B 70 68 C 79 75 D 76 75 E 93 94 F 84 80 G 88 75 H 77 76 68 72 - - 81 78 K 84 76 L 87 80 M 62 65 N 90 87 O 78 75 P 85 80 a. Conduct a hypothesis test using the data above. On Backboard, you will be asked: (i) What is the value of the parameter based on the null hypothesis? (ii) What are the degrees of freedom? (iii) What is the critical value? (iv) What is the estimated variance? (v) What is the estimated standard error? (vi) What is the calculated t statistic? (vii) Did you reject the null hypothesis? (Yes/No) b. Compute a 95% confidence interval to the mean difference. (i) What is the lower boundary? (ii) What is the upper boundary