An electrical firm manufactures light bulbs that have a life

An electrical firm manufactures light bulbs that have a lifetime that is approximately normally distributed with a mean of 800 hours and a population standard deviation of 40 hours. In a random sample of 30 bulbs, the mean lifetime is 788 hours. Suppose you are asked to conduct a hypothesis test to determine if the mean lifetime of the bulbs is different from 800 hours. What null and alternative hypotheses would you use to conduct this test? What type of test statistic would you use to conduct this test? Suppose the p-value for this hypothesis test is 0.1003. If a = 0.05, what would your decision and conclusion be for this test?

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