Auto Fuel Efficiency. As part of a study designed to compare hybrid and similarly equipped conventional vehicles, Consumer Reports tested a variety of classes of hybrid and all-gas model cars and sport utility vehicles (SUVs). The following data show the miles-per-gallon rating Conswmer Reports obtained for two hybrid small cars, two hybrid midsize cars, two hybrid small SUVs, and two hybrid midsize SUVs; also shown are the miles per gallon obtained for eight similarly equipped conventional models.
$$
\begin{array}{lllc}
\text { Make/Model } & \text { Class } & \text { Type } & \text { MPG } \\
\text { Honda Civic } & \text { Small Car } & \text { Hybrid } & 37 \\
\text { Honda Civic } & \text { Small Car } & \text { Conventional } & 28 \\
\text { Toyota Prius } & \text { Small Car } & \text { Hybrid } & 44 \\
\text { Toyota Coralla } & \text { Small Car } & \text { Conventional } & 32 \\
\text { Chevrolet Malibu } & \text { Midsize Car } & \text { Hybrid } & 27 \\
\text { Chevrolet Malibu } & \text { Midsize Car } & \text { Conventional } & 23 \\
\text { Nissan Altima } & \text { Midsize Car } & \text { Hybrid } & 32 \\
\text { Nissan Altima } & \text { Midsize Car } & \text { Conventional } & 25 \\
\text { Ford Escape } & \text { Small SUV } & \text { Hybrid } & 27 \\
\text { Ford Escape } & \text { Small SUV } & \text { Conventional } & 21 \\
\text { Saturn Vue } & \text { Small SUV } & \text { Hybrid } & 28 \\
\text { Saturn Vue } & \text { Small SUV } & \text { Conventional } & 22 \\
\text { Lexus RX } & \text { Midsize SUV } & \text { Hybrid } & 23 \\
\text { Lexus RX } & \text { Midsize SUV } & \text { Conventional } & 19 \\
\text { Toyota Highlander } & \text { Midsize SUV } & \text { Hybrid } & 24 \\
\text { Toyota Highlander } & \text { Midsize SUV } & \text { Conventional } & 18 \\
& & &
\end{array}
$$
At the $\alpha=.05$ level of significance, test for significant effects due to class, type, and interaction.