If it is in proper adjustment, the metal stamping machine at the Ockham Razor company produces carbon blades that, on average, are 18 mm in thickness, with a standard deviation of .5 mm. You take measurements on a random sample of 49 blades every hour in order to judge whether the machine continues to function properly or has slipped out of adjustment and is producing blades that are either too thick or too thin. Suppose at 11: 00 A. M. you take a random sample of 49 blades and find that the average thickness for the sample is 17.96 mm. Conduct an appropriate two tailed hypothesis test and report your conclusion. Assume the population standard deviation is .5 mm. Use a significance level of .01.