108 Stress and diet study. Researchers at the University of South Florida investigated the effects of diet on the physiology and behavior of rats ( USF News , Oct. 17, 2009).

One group of rats was fed a typical American diet (40%

fat, 40% protein, 20% carbohydrates); a second group of rats was fed an Atkins-type diet (70% fat, 20% protein, 10% carbohydrates); and, a third (control) group was fed rat chow. Assume the experiment utilized 50 rats. Use a random-number generator to randomly assign the rats to the three diet groups.