The life in hours of a 75-watt light bulb is known to be normally distributed with o = 24hours. A random sample of 25 bulbs has a mean life of x = 1500 hours. (a) Construct a 9X% two-bounds sided confidence interval on the mean life. (b) Construct a 9X% lower confidence bound on the mean life. (c) Construct a 95% upper confidence bound on the mean life. (d) Find the sample size such that the maximum error (E) in both sides is 2 hours

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