According to the text, in the U.S. today, the period of middle adulthood spans the ages from:

What may play a role in the onset of BBD when physical appearance is reinforced in early life?

a. operant conditioning b. delayed conditioning c. social cognitive conditioning d. classical conditioning

Actions that help others with no direct benefit to the individual are known as

a. empathy. c. role-taking. b. antisocial. d. altruism.