By what age has an infant begun to understand the emotions that lie behind facial and vocal expressions of others?

A correlation of .50 between school grades and IQ scores means that __________ percent

of the variance in school grades is NOT explained by IQ scores. a. 10 b. 25 c. 40 d. 75 e. 90

A disorder in which intruding thoughts that occur again and again are followed by repetitive, ritualistic behavior meant to lower the anxiety caused by the thoughts is called __________ disorder

a) obsessive-compulsive b) delusional c) post-traumatic stress d) passive-aggressive