Answer to Question 1
positive reinforcer
Answer to Question 2
Different processes are involved in extinction, time-out, and response cost. With extinction, the problem behavior is no longer followed by the reinforcing event that previously maintained the problem behavior. With time-out, the individual is removed from access to all sources of reinforcement contingent on the problem behavior. With response cost, a specific amount of a reinforcer (but not the reinforcer for the problem behavior) is removed following the problem behavior.