An anonymous survey of college students was taken to determine behaviors regardingalcohol, cigarettes, and illegal drugs. The results were asfollows: 849 drank alcoholregularly, 662 smokedcigarettes, 201 used illegaldrugs, 409 drank alcohol regularly and smokedcigarettes, 109 drank alcohol regularly and used illegaldrugs, 110 smoked cigarettes and used illegaldrugs, 87 engaged in all threebehaviors, and 329 engaged in none of these behaviors.