Bartenders who put some dollar bills in their tip jars in order to influence their customers to tip generously are trying to take advantage of which social influence principle?

A gray card in sunlight looks darker than a white card in the shade. This is an example of

a. brightness constancy. b. form constancy. c. habituation. d. counterbalancing. e. the phi phenomenon.

Which brain structure allows us to pay attention to certain stimuli while ignoring others?

a. medulla b. cerebellum c. reticular formation d. pons