Roger has a vacant stare. He answers questions in an apathetic, monotonous voice, and shows no emotion, even when discussing events such as his mother's death. Roger's affect would be described as

The first outward sign of puberty in a typical girl is

a spurt in height. the onset of nipple growth. an increase in weight. the development of muscular strength.

Thomas Young was essentially correct when he hypothesized that the eye contains

__________ types of color receptors that respond to __________. a. three; red, green, and blue b. three; black, white, and gray c. six; the spectral colors d. two; red/green and yellow/blue e. three; red, yellow, and blue