Until the Council of Trent in 1563, the Catholic Church accepted as a marriage any public statement by a couple that they considered themselves married to each other. What were the necessary conditions for this?

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.