George Miller found that the average person is able to keep about _______ digits in mind at a time

The fact that sensory systems are need-specific is demonstrated by which of the following examples?

a. Giraffes need to eat the leaves from trees, and so they have developed a long neck so they can reach food. b. Human beings have evolved past their need for an appendix, so that organ can be removed without any negative impact. c. Bats hunt in the dark so they use echolocation instead of eyesight to track down prey. d. Roaches have learned that they are safest in dark locations where they cannot be seen by human beings, so they stay in floors and walls where they will not be detected.

Which of the following is a type of photoreceptor found in the retina?

a. Cones b. Ganglion Cells c. Amacrines d. Chiasms