A manufacturer of car batteries claims that the life of the company’s batteries in years is...

A manufacturer of car batteries claims that the life of the company’s batteries in years is approximately normally distributed with a population variance of 0.81. A random sample of 10 of these batteries has a variance of 1.44. Construct a 95% C.I. for . Use and to construct the interval.

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. A manufacturer of car batteries claims that the life of his batteries is approximately normally...

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