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The average price of a college math textbook is $158 and the standard deviation is 524. Suppose that 42 textbooks are randomly chosen. Round all answers to 4 decimal places where possible. a. What is the distribution of I? I - N( b. For the group of 42, find the probability that the average price is between $157 and $160. C. Find the third quartile for the average textbook price for this sample size. $ round to the nearest cent) d. For part b), is the assumption that the distribution is normal necessary? ( Yes No