Sap is a substance secreted by some trees. Many years ago, plants and small animals were caught in the sap on the trees. Sap hardens and turns into a clear substance called amber. The plants or animals are preserved as fossils in the amber. Part of a plant preserved in amber is shown . Explain why fossils are important to scientists.

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.