To add 8 + 5, Billy breaks down the 8 into 5 + 3. He then adds this 5 to the first 5 to get 10, then he adds the remaining 3 to get 13. Researchers might say that Billy used the strategy of

MDMA, or methylene-dioxy-methamphetamine, is the chemical name for which popular street drug?

a) LSD b) slippies c) Ecstasy d) hashish

Dr. Smith believes people who are very aggressive have become so because of their life experiences. Dr. Jones believes people are more or less aggressive from birth because of genetic factors. What issue in developmental psychology is highlighted by their disagreement?

a) nature and nurture b) cognition and emotion c) classical and operant conditioning d) cross-sectional studies and longitudinal design