Although four similar-sized small-car models exhibit similar miles per gallon (mpg) sticker ratings, there is some skepticism as to whether their mean mpg values are really equal. To test this equal-means hypothesis, several cars of each model are driven for 10,000 miles under nearly identical driving conditions. The observed mpg values are listed in the file P12_5.XLS. Use one-way ANOVA to help decide whether the different models have equal mean mpg values, and write a short report to summarize your findings.