<span>Piaget's theory
of development assumed that all children pass through a series of four
universal stages in a fixed order from birth to adolescence. these are sensorimotor, preoperational, concrete operational, and formal operational. <span>These
stages are determined by an observable neurological development that
allows children to acquire diverse and more advanced thought processes.
I hope my answer can help you.
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In general, politicians pay the most attention to middle-age white people in elections, since they believe they are the most active voters, instead of the very young and the very old.
Serfs paid the owner of the land (in the form of labor) to be able to live on the land and have protection, if the serf were to leave. It was usually an unspoken agreement that they serf would stay on the land. If you still need further information you might find some on http://www.thefinertimes.com/Middle-Ages/serfs-in-the-middle-ages.html
