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In a sample of 65 electric motors, the average efficiency (in percent) was 85 and the...

In a sample of 65 electric motors, the average efficiency (in percent) was 85 and the standard deviation was 2.

a) Find a 98% lower confidence bound for the mean efficiency. Round the answer to two decimal places.
b) The claim is made that the mean efficiency is greater than 84.615%. With what level of confidence can this statement be made? Express the answer as a percent and round to two decimal places.The level of confidence is ???????? %.

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