A(n) is a material that cannot be broken down into anything to by chemical reactions

Psychologists studying infant memory want to determine at what age babies can remember specific events. an experimenter uses several puppets to demonstrate a series of actions while the infant watches. after a delay, the experimenter records how many of the actions the child imitates when playing with the puppets. what is the dependent variable?

What was the social class pyramid during the civil war?

How has our understanding of the first sentence of the declaration of independence changed over time?