How do we calculate the 95% confidence interval for the mean with the population standard deviation known for an upper and a lower confidence limit? Please describe what happens if calculated at the 99% confidence interval and for the 80% confidence interval. How does the increase in the confidence level change the width of the confidence interval?

The means or the average. X = 84

The standard deviation from 73 inches to 95 inches (divided by 6). s = 3.667

The sample size. n = 100.