13. The Ofce of Student Services at a large western state university maintains information on the study habits of its full-time students. Their studies indicate that the mean amount of time undergraduate students study per week is 15 hours. The hours studied follows the normal distribution with a standard deviation of six hours. Suppose we select a random sample of 144 current students. What is the probability that the mean of this sample is between 14.25 hours and 16.0 hours? 14. The Intelligence Quotient (IQ) test scores for adults are normally distributed with a mean of 100 and a stande deviation of 15. What is the probability we could select a sample of 100 adults and nd the mean of this sample is less than 95