You have three identically sized crackers. You place two of them in front of you and one in front of a child who is in Piaget's preoperational stage. The child agrees that you have more crackers than he does. If you now break the child's cracker into two equal pieces and ask who has more, he will say:. a. you still have more.
b. he has more.
c. his crackers are smaller.
d. you both have the same.

C.  his crackers are smaller.

Explanation:

The preoperational stage is piagets second stage in his theory of operational development. This stage is from  two years of age to 7 years. The young children at this age are able to think more symbolically with their memory and imaginations being developed. The child at this stage learns to conserve mass so they would be able to recognize that their cracker is smaller than yours.

answer:

d. because dr. laguardia selected a widely used measure, his study generalizes to has strong external validity. external validity has limited external validity. other applications of this measure.

the widely used measure that he applied to his experiment was the benton facial recognition test. it employed on to football players and as result, only players who suffered brain concussions did not pas this test. and although it has an external validity, it is limited because it isn't general to apply to other population.

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