A sample of 250 observations is selected from a normal population for which the population standard deviation is known to be 23. The sample mean is 19.
A. Determine the standard error of the mean. (Round your answer to 3 decimal places)
Standard error of the mean __________
B. Determine the 98% confidence interval for the population mean. (Round your answers to 3 decimal places)
Confidence interval _______and_______