ER The mean playing time for a large collection of compact discs is 33 minutes, and the standard deviation is 3 minutes. (a) What value (in minutes) is 1 standard deviation above the mean? One standard deviation below the mean? What values are 2 standard deviations away from the mean? 1 standard deviation above the mean 1 standard deviation below the mean min min 2 standard deviations above the mean 2 standard deviations below the mean min Imin (b) Assuming that the distribution of times is mound shaped and approximately symmetric, approximately what percentage of times are between 27 and 39 minutes? (Hint: See Example 3.19. Use the Empirical Rule.) % Less than 24 min or greater than 42 min? % Less than 24 min? %