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Question Help A simple random sample of size n is drawn from a population that is normally distributed. The sample mean, x, is found to be 111, and the sample standard deviation, s, is found to be 10. (a) Construct a 98% confidence interval about u if the sample size, n, is 19 (b) Construct a 98% confidence interval about u if the sample size, n, is 23. (c) Construct a 99% confidence interval about u if the sample size, n, is 19. (d) Could we have computed the confidence intervals in parts (a)-(c) if the population had not been normally distributed? Click the icon to view the table of areas under the t-distribution. (a) Construct a 98% confidence interval about u if the sample size, n, is 19. Lower bound: Upper bound: (Use ascending order. Round to one decimal place as needed.)