Marital conflict and distress tend to be associated with an increased risk for __________, especially among women

At birth, the percentage of total body length accounted for by head and legs respectively is

A. 15 and 25 B. 25 and 45 C. 25 and 15 D. 45 and 25

Which of the following is a conditioned positive reinforcer?

a. money b. sex c. food d. warmth