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10. With gasoline prices increasing, drivers are becoming more concerned with their cars' gasoline consumption. For the past 5 years, a driver has tracked the gas mileage of his car and found that the variance from fill-up to fill-up was o^2= 20 mpg^2. Now that his car is 5 years old, he would like to know whether the variability of gas mileage has changed. He recorded the gas mileage from his last eight fill-ups; these are listed here. Conduct a test a 5% significance level to infer whether the variability has changed. (10 points) 25, 23, 26, 25, 22, 27, 26, 24