What was the Life around an oasis in uae in the past

The physical feature that makes up part of the border between canada and the united states is the

17 points! ! (explain your answer)

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.