The 2009 National Survey on Drug Use and Health selected a random sample of U.S. college students and asked them if they had ever used illicit drugs. Approximately 23% of the students surveyed reported using illicit drugs in the past year. Thevariable in this study is:
◦
the percentage of students who reported using illicit drugs.
◦
whether a student used illicit drugs.
◦
whether a college student responded to the survey.
◦
the number of college students who use illicit drugs.