For Piaget, the most fundamental deficiency of preoperational thinking is egocentrism, which is .

hygrometers and hair thermometers (often found as part of hygrometers/psychrometers) can be used to measure humidity. barometers are used to measure atmospheric pressure, while anemometers are used to measure wind speed. so the 2nd and 4th choices should be the correct answers.

answer; adjusting and adapting to a culture other than one's own;

answer; size, shape, color and status;