Descriptive Statistics Variable N Mean SD Mileage 75 16967 7401.6 @ Also, list your size/mileage for your 20th and your 40th observation below. For all of question 2, treat these values as the mean and standard deviation of the population when answering questions. Size/Mileage for Observation #20: Size/Mileage for Observation #40: a. For this problem, assume that the distribution: for all sizes/mileages in the population are normally distributed (may not really be true). Find the proportion of all sizes/mileages that Would fall between the sizeslmileages of your 20th and 40th observations. To receive full credit, you should include pictures of the normal curve (labeled with both x and 2- values) with the pertinent probabilities shaded in the picture. Descriptive Statistics Here X .2 b. Assuming the distbution of the sizeslmileages are normal, use the mean and standard deviation you found above to locate the 9th percentile in the size/mileage distribution. To receive full credit, you show as much work as possible. I c. Suppose you 'take a future sample of 100 sizes/mileages from your population. Describe the sampling distribution for the xbar value that you would nd. (hint: there should be three parts to this answer) _ . .. . . .u. .n . u . o .u . r