1. A manufacturer produces light bulbs that have a mean life of 500 hours when the production process is working properly. Based on experience, the population standard deviation is 50 hours and the light bulb life is normally distributed. The operations manager stops the production process if there is evidence that the population mean light bulb life is not equal to 500 hours.Please label each answer section with the corresponding letter.

b. Using a level of significance =0.05, what are the rejection and non-rejection regions in the unit of hours if we use the sample mean of 100 randomly selected light bulbs as the test statistic?

How do you calculate X_bar to calculate the test stastic? What formula is used?