Mirena wants is interested in the effects of gender on aggression. She collects all the studies she can find that have been conducted on this topic, and averages their results to generate a big picture of what the findings in that area reveal. Mirena has conducted a ____

After reading about the possible causes of schizophrenia, a scientist thinks that a virus is the most likely cause. What term most accurately describes the scientist's idea?

a) hypothesis b) dependent variable c) extraneous variable d) experimental estimate

People awakened during REM sleep report vivid, graphic dreams ________ percent of the time

a. 80 to 85 b. 40 to 45 c. 60 to 65 d. 20 to 25