By 4 years of age, it is estimated that children use correct grammar in what percentage of their statements?

Which of the following is a new kind of eating disorder that is found almost exclusively in men?

a.) Muscle dysmorphobia b.) Binge-eating disorder c.) Abdominal dissatisfaction disorder d.) Non-binging bulimotoxicity

REM sleep refers to __________________

a) dreamless sleep b) sleep induced by sleeping pills c) sleep periods in which sleepwalking is likely d) sleep periods in which a person's eyes move rapidly