Exam Number: 350366 Answer any two of the following four questions. Each answer is worth 15 percent. 1. You've started recording how long your cell phone battery lasts between charges. You find that the length of time between charges, x, is normally distributed with a mean of 10 hours and a standard deviation of 1.5 hours. What is the probability that your cell phone battery will last between 8 and 12 hours between charges? 2. A university asked 10 graduate students how many hours of homework they were planning to do that week. Here are their responses: 14 13 15 21 19 24 25 28 25 31 Answer the following questions about this data: a. What's the mean number of hours of homework done by these students per week? What's the median? Why are these figures different? b. What's the range of the data? c. Is the data skewed? If so, in what direction? How do you know