Question: Airplane tires are sensitive to the heat produced when the plane taxis along runways. A certain type of airplane tire used by Boeing is guaranteed to perform well at temperatures as high as 125°F. From time to time, Boeing performs quality control checks to determine whether the average maximum temperature for adequate performance is as stated, or whether the average maximum temperature is lower than 125°F, in which case the company must replace all tires. Suppose that a random sample of 100 tires is checked. The average maximum temperature for adequate performance in the sample is found to be 121°F and the sample standard deviation 2°F. Conduct the hypothesis test, and conclude whether the company should take action to replace its tires.