At a local restaurant, the amount of time that customers have to wait for their food is normally distributed with a mean of 38 minutes and a standard deviation of 4 minutes. Using the empirical rule, determine the interval of minutes that the middle 99.7% of customers have to wait.

Mozart lenses inc. recently introduced seelites, a thinner lens for eyelasses. of a sample of 800 eyeglass wearers, 246 said they would purchases their next pair of eyeglasses with the new lenses. lenses inc. estimates that the number of people who purchase eyeglasses in a year is 1,700,000. most eyeglasses wearer buy one new pair of eyeglasses a year. what is the annual sales potential for the new lenses.