Highway Fuel Consumption Data Set 14 in Appendix: Data Sets lists highway fuel consumption amounts (mi/gal) for cars categorized by size (small, midsize, large). If we use those highway fuel consumption amounts arranged into the three separate size categories, we get the XLSTAT results shown in the following display. Using a 0.05 significance level, test the claim that the three size categories have the same mean highway fuel consumption. Does the size of a car appear to affect highway fuel consumption?

XLSTAT Analysis of variance: Source DF Sum of squares Mean squares F Pr> F 224.095 112.048 11.610 0.001 9.651 Model 12 Error 18 173.714 Corrected Total 20 397.810