Business Weekly conducted a survey of graduates from 30 top MBA programs. On the basis of the survey, assume the mean annual salary for graduates 10 years after graduation is $164,000. Assume the standard devlation is $44,000. Suppose you take a simple random sample of 18 graduates. Round all answers to four decimal places if necessary. a. What is the distribution of X? X - NO b. What is the distribution of ? 2 - N c. For a single randomly selected graduate, find the probability that her salary is between $150,944 and $165.629. d. For a simple random sample of 18 graduates, find the probability that the average salary is between $150.944 and 5165,629. e. For part d), is the assumption of normal necessary? O Yes No