The following data represent the scores of a sample of 50 randomly chosen students on a standardized test.
39 48 55 63 66 68 68 69 70 71
71 71 73 74 76 76 76 77 78 79
79 79 79 80 80 82 83 83 83 85
85 86 86 88 88 88 88 89 89 89
90 91 92 92 93 95 96 97 97 99
a. Write a 95% confidence interval for the mean score of all students who took the test.
b. Identify the target parameter and the point estimator.