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eld Corporation products just about everything but is currently interested in the lifetimes of its batteries, hoping to obtain its share of a market boosted by the popularity of portable CD and MP3 players. To investigate it's now line of Ukra batteries, BIG randomly selects 1000 Ultra batteries and finds that they have a mean lifetime mean lifetime of 912 hours, with a standard deviation of 99 hours. Suppose that this mean and standard deviation apply to the population of all Ultra batteries. Complete the following statements about the distribution of lifetimes of all Ultra batteries. [a) According to Chebyshew's theorem, at least 56 of the lifetimes lie between 714 hours and 1110 hours. (b) According to Chatryshaw's theorem, at least 84% of the life hours and_ _hours. (found your answer to the nearest integer.] between () Suppose that the distribution is bell-shaped. According to the empirical rule, approximately 68% of the lifetimes Bie hours and hours. d) Suppose that the distribution is bell- empirical rule, appro of the lifetimes Its behacen 714 hours and 11 10 hours a. 69% b b. 75% c. 95% d. 99.7%%