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QUESTION 6 A researcher studied whether meeting regularly with a weight-loss counselor helps dieters lose weight. Eighty dieters were available for the study. Half the dieters, assigned at random, received weight-loss counseling. The other half did not. After six months, the weight lost by each dieter was measured. On the average, those who met regularly with a weight-loss counselor lost more weight than those who did not. The explanatory variable is a. whether or not the dieter received weight-loss counseling O b. whether or not the dieter lost weight O c. The total weight loss d. the weight lost by each dieter QUESTION 7