9) At a particular university, the number of hours a student spends studying in a week is normally distributed with a mean of 15 hours and a standard deviation of 4 hours. If a student is selected at random, find the probability that he or she will spend between 20 and 25 hours studying next week. a) 0.0994 b) 0.1249 0) 0.1056 01) 0.1118 e) 0.0300