Limiting factors help regulate the size of a population. Which of these limiting factors does not depend upon the density of a population?

A. food
B. a natural disaster
C. space
D. disease

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.