Does the Weight of a Car Affect Head Injuries in a Crash? Data were obtained from car crash experiments conducted by the National Transportation Safety Administration. New cars were purchased and crashed into a fixed barrier at 35 mi h, and measurements were recorded for the dummy in the driver’s seat. Use the sample data listed below to test for differences in head injury measurements (in hic) among the four weight categories. Is there sufficient evidence to conclude that head injury measurements for the four car weight categories are not all the same? Do the data suggest that heavier cars are safer in a crash?

Subcompact: 681 428 917 898 420 Compact: 643 655 442 514 525 Midsize: 469 727 525 454 259 Full-size: 384 656 602 687 360