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A machine that produces plastic jar lids is set to produce lids with a diameter of 9 cm. The standard deviation of the diameters, due to the production process, is 0.02 cm. A quality-control worker checks a sample of 25 lids from each production run and finds the mean diameter. One day, the mean diameter for the sample is 8.99 cm. Find a 95% confidence interval for the true mean diameter of lids produced that day.
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