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The quality control manager of an electronics manufacturer needs to estimate the mean life of one of its products using a sample drawn from a large shipment of the product. The standard deviation of the product's life is known to be 375 hours. A random sample of 55 units indicated a sample mean life of 2,333 hours. If an exact Z-value (or t-value) is not available in the appropriate table, use the closest value. However, if an exact value can be interpolated (e.g. 1.645 for.95), use that value. Round/report your final value (do not round your intermediate values) to four (4) decimal places. a. Set up a 99% confidence interval estimate of the true population mean life of the product using this shipment. Z-Value or t-value (whichever is appropriate) Lower Confidence Interval Value Upper Confidence Interval Value b. Does the manufacturer have the right to state that the product will last an average of 2,450 hours? Type Yes or NO