A random sample of 23 items is drawn from a population whosestandard deviation is unknown. The sample mean is x=820 and thesample standard deviation is s=25. (Round all answers to 3 decimalplaces)
(a) Construct an interval estimate of u with 99% confidence
(b) Construct an interval estimate of u with 99% confidence,assuming that s=50
(c) Construct an interval estimate of u with 99% confidence,assuming that s=100
