To estimate the parameter stated in question 2, the following was done. A simple random sample of 22 students who attended a review session was selected, and the mean grade on test 7 for this sample of 22 students was 85 with a standard deviation of 9.8. An independent simple random sample of 47 students who did not attend a review session was selected, and the mean grade on test 7 was 77 with a standard deviation of 10.6. If appropriate, use this information to calculate and interpret a 90% confidence interval for the difference in the mean grade on test 7 for all students who attended a review session and for all students who did not attend a review session. interpret a 90% confidence interval for the difference in the mean grade on test 7 for all students who attended a review session and for all students who did not attend a review session. B I. VA - A TXE 를 들 12pt Paragraph x? X Х. fr we are 90% confident that the true difference between population means is continued by the interval (3.72424, 12.27576) -. (6 points) Consider the same populations as defined above question 2. Of interest is to test the hypothesis that the mean grade on test 7 for all students who attended a review session and the mean grade on test 7 for all students who did not attend a review session are the same, versus the alternative hypothesis that the mean grade on test 7 for all students who attended a review session is greater than the mean grade on test 7 for all students who did not attend a review session. State the appropriate null and alternative hypotheses that should be tested.