11. Joe was exhibiting problematic behavior at school. The other students enjoyed Joe's antics and thought he was funny. However, the teacher found his behavior disruptive and often sent him to the principal, who was unable to affect his behavior despite many disciplinary attempts. Explanation: Joe's behavior has been shaped by the environment—the reactions of the other children, the teacher, and the principal all served to reinforce the disruptive behavior and make it more likely to occur.