Mrs. Pearson cut Judy's hot dog into eight pieces and Sylvia's into six pieces. Sylvia cried because she felt she wasn't getting as much hot dog as Judy. Piaget would say that Sylvia doesn't understand the principle of ___.

Conservation

Explanation:

Conservation is a concept that was proposed by Jean Piaget in cognitive development theory. This concept was found in the pre-operational stage around 2 to 7 year age. It is logical thinking. In this concept children developed logical thinking for certain quantity despite the size, the shape has been changed. The conservation concept is related to logical thinking in children.  

Thus in the above statement, when Mrs. Pearson cut the hot dog in eight pieces for Judy and six pieces for Sylvia. Sylvia starts to cry, she thought Judy much than her because she does not develop her conservation concept related to the number of things.  

for many centuries there were important factors which the economies of the muslim empires developed increasingly. they applied economic procedures in production, investment, finance, taxation and property. they used to tax certain goods (for example: harvest), they charged interest on money lent, they signed contracts with merchants; they relied on a common currency, and they used checks as well as promissory notes. with the money collected by means of taxation, the government provided the needy with an income. in addition, trading networks covered huge distances, so far regions started to have contact and exchange goods. this trade network covered areas of asia, africa and europe.

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