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(9 pts) For a particular model of a car, currently the mean gas mileage is 26 miles per gallon on the highway. Automotive engineers want to use more aluminum to improve gas mileage. In a sample study of n=25 cars made with more aluminum, the mean mileage is x= 28.04 mpg and the standard deviation is s= 5.00 for highway driving. Is there sufficient evidence to conclude that by using more aluminum, the mean highway mpg will improve i.e., u > 26? Use o = 0.05. (Assume the population distribution is normal)