The thickness of a plastic film (in mils) on a substrate material is thought to be influenced by the temperature at which the coating is applied. A completely randomized experiment is carried out. Eleven substrates are coated at 125 F, resulting in a sample mean coating thickness of x, = 103.5 and a sample standard deviation of s, = 10.2. Another 13 substrates are coated at 150*F, for which x2 = 99.7 and $2 = 20.1 are observed. You are suspicious that raising the process temperature would reduce mean coating thickness. Use Ha: #1 > /2 for the alternate hypothesis and a= 0.01. Assume that both populations are normally distributed the two population standard deviations are not equal.5. Critical Value: Determine critical value(s) and put on graphic