Two toddlers are playing tag. "I chase you!" shouts one to the other. "You chase me.". says the second one in reply. The fact that one child is acting as "chasee" and the other as "chaser" in this tag game illustrates

Betty was born with deformities of the arms and legs, as well as damage to her heart and kidneys. She scores below average in intelligence

Based on the damage to the developing organism, you could conclude that Betty's mother took __________ while pregnant. A) diethylstilbestrol (DES) B) Accutane C) aspirin D) thalidomide

Which of the following is a control for experimenter expectancies?

A) use of instruments and automation B) carefully prepared scoring instructions C) single-blind experiment D) carefully prepared instructions for participants E) all of the above