The U.S. Department of Energy’s Fuel Economy Guide provides fuel efficiency data for cars and trucks (Fuel Economy website). A portion of the data from 2018 for 341 compact, midsize, and large cars is shown in Table 2.13. The data set contains the following variables: 

Size: Compact, Midsize, and Large 

Displacement: Engine size in liters Cylinders: Number of cylinders in the engine 

Drive: All wheel (A), front wheel (F), and rear wheel (R) 

Fuel Type: Premium (P) or regular (R) fuel 

City MPG: Fuel efficiency rating for city driving in terms of miles per gallon 

Hwy MPG: Fuel efficiency rating for highway driving in terms of miles per gallon 

The complete data set is contained in the file FuelData2018. 

a. Prepare a crosstabulation of the data on Size (rows) and Hwy MPG (columns). Use classes of 20–24, 25–29, 30–34, 35–39, and 40–44 for Hwy MPG. 

b. Comment on the relationship between Size and Hwy MPG. 

c. Prepare a crosstabulation of the data on Drive (rows) and City MPG (columns). Use classes of 10–14, 15–19, 20–24, 25–29, and 30–34 for City MPG. 

d. Comment on the relationship between Drive and City MPG. 

e. Prepare a crosstabulation of the data on Fuel Type (rows) and City MPG (columns). Use classes of 10–14, 15–19, 20–24, 25–29, and 30–34 for City MPG. 

f. Comment on the relationship between Fuel Type and City MPG. 

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TABLE 2.13 Fuel Efficiency Data for 341 Cars Fuel City MPG Hwy MPG Car Size Displacement Cylinders Drive Туре 1 Compact Compact Compact 1.4 4 F R 27 40 1.4 4 F 27 35 3 1.4 4 28 38 190 2.5 Compact Large 4 27 36 191 2.5 4 22 30 192 Midsize 2.5 4 21 32 339 6.0 Large Large Large 12 13 21 340 6.0 12 13 22 341 6.0 12 13 20 R RR •R RR ... PP LL LL L •R RR