The National Collegiate Athletic Association (NCAA) reported that the mean number of hours spent per week on coaching and recruiting by college football assistant coaches during the season was 70.

A random sample of 50 assistant coaches showed the sample mean to be 68.6 hours, with a sample standard deviation of 8.2 hours.

Parts "a" and "b" - Confidence Interval:

1. (5 points) Using the sample data, calculate the CONFIDENCE INTERVAL for the population mean at a 99% confidence level. Be sure to show all steeps of your calculations.

1. (1 point) Does the CONFIDENCE INTERVAL include the value suggested by the NCAA? Why?

Parts "c" and "d" - Suppose you decided to lower the confidence level from 99% to 95%:

1. (2 points) Without performing any calculations, will the CONFIDENCE INTERVAL increase, decrease, or stay the same? Why?
2. (2 points) Which of the terms in Eq. 9-2 will change? Will it increase or decrease? Why?