Big Corporation produces 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 its new line of Ultra batteries, BIG randomly selects 1000 ultra batteries and finds that they have a mean lifetime of 826 hours, with a standard deviation of 90 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 chebyshev's theorem, at least 84% of the lifetimes lie between____ hours and_____hours. (Round your answer to the nearest integer.)

B.) According to chebyshev's theorem, at least_____of the lifetimes lie between 646 hours and 1006 hours.

C.) Suppose that the distribution is bell-shaped. According to the empirical rule, approximately____of the lifetimes lie between 646 hours and 1006 hours.

D.) Suppose that the distribution is bell-shaped. According to the empirical rule, approximately 68% of the lifetimes lie between_____hours and_____hours.