Alexandra and Anders are playing a game where Anders hides a stuffed animal and Alexandra tries to find it. When she does, Alexandra hides the stuffed animal and Anders tries to find it. This is an example of play.

Which statement is a good description of a model? a) models are a description of nature based only on one or two variables. b) models are testable ideas but they are not very to most people. c) models are a description of nature that predicts more accurately than real events. d) models are an approximiation of a real system that omits all but most essential variables in a system.