还有一题

The Acculturation Rating Scale for Mexican Americans (ARSMA) measures the extent to which Mexican Americans have adopted Anglo/English culture. During the development of ARSMA, the test was given to a group of 17 Mexicans. Their scores, from a possible range of 1.00 to 5.00, had x = 1.67 and s = 0.25. Because low scores should indicate a Mexican cultural orientation, these results helped to establish the validity of the test. (a) Give a 95% confidence interval for the mean ARSMA score of Mexicans. (b) What assumptions does your confidence interval require? Which of these assumptions is most important in this case?