Holiday walks home from work everyday. In three years she has worked at the hospital, she will not step on a crack in the sidewalk. This is an example of:

When Jan helped her mother clean up after her baby brother, Jan's mother praised her daughter for being so thoughtful. For Jan, her mother's praise is serving as a

a. positive reinforcer. b. negative reinforcer. c. primary reinforcer. d. response cost.

According to APA guidelines, which phrase should be used to refer to people who have a psychological problem or mental illness?

a. mentally ill people b. psychologically disturbed people c. the mentally ill d. people who have a mental illness e. psychologically troubled individuals