REM sleep, or ‘active sleep' constitutes what percentage of a normal night's sleep in adults?

An empirical scale is constructed using

a. actual clinical data. b. theoretical models. c. answers from people with no previously identified symptoms. d. the emperor's method.

Compared with adult mothers, adolescent mothers ________

A) know more about child development B) perceive their babies as more difficult C) less often engage in abusive parenting D) interact more effectively with their infants