Assignment:
A telephone company wants to estimate the average length of long-distance calls during weekends. A random sample of 50 calls gives a mean x = 14.5 minutes and standard deviation s = 5.6 minutes. Give a 95% confidence interval and a 90% confidence interval for the average length of a long-distance phone call during weekends.
Your answer must be typed, double-spaced, Times New Roman font (size 12), one-inch margins on all sides, APA format and also include references.