CI forpopulation mean:

1. N.Arshadiand E. Lawrence investigated the profiles of the top executives in the U.S. banking industry. They sampled 30 executives with respect to the number of years of service at the same bank, the group had a sample mean of 23.43and the same standard deviation s= 10.82 years. Construct a 99% confidence interval for the mean service time for all top executives in the banking industry.
2. The following data represent the age (in weeks) at which babies' first crawl based on a survey of 12 mothers conducted by Essential Baby. Construct and interpret a 95% confidence interval for the mean ageat which a baby first crawls.

52	30	44	35	39	26
47	37	56	26	39	28