The National Weather Service says that the mean daily high temperature for October in a large midwestern city is 56°F. A local weather service suspects that this value is not accurate and wants to perform a hypothesis test to determine whether the mean is actually lower than 56°F. A sample of mean daily high temperatures for October over the past 36 years yields Assume that the population standard deviation is 5.6° F. Perform the hypothesis test at the significance level.