A company advertised that its electric motors provide an efficiency that is at least 25% higher than the industry norm. A consumer interest group ran an experiment with a sample of 23 machines that had a sample mean of 22.8% and a standard deviation of 8.72%. i. Determine if the consumer interest group has evidence that the advertised claim is false. ii. Find the 98% two-sided confidence interval for the average efficiency of the electric motors. Comment on your answer.

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