Suppose that the average number of Facebook friends users have is normally distributed with a mean of 128 and a standard deviation of about 46. Assume eighteen individuals are randomly chosen. Answer the following questions. Round all answers to 4 decimal places where possible.

1. What is the distribution of xx? xx ~ N(,)
2. For the group of 18, find the probability that the average number of friends is more than 117.
3. Find the first quartile for the average number of Facebook friends.
4. For part b), is the assumption that the distribution is normal necessary? NoYes