What is the leading cause of death in the U.S.?

Carter’s mother turned her head suddenly as the dog approached from behind. Carter was watching his mother’s face and turned in the same direction. This aspect of infant-adult communication is known as

a. simple imitation. b. joint attention. c. the language acquisition device. d. home sign.

Honig and Slivka trained pigeons to peck discs of various colors. After this they began shocking the birds when they pecked a disc of a particular color. This __________

a. reduced pecking on that disc, but not discs of other colors b. reduced pecking discs of all colors, but especially those that resembled the punished color c. had no effect on the rate of pecking d. reduced pecking on discs of the punished color, but increased pecking on other discs