Question

question 3 review the responses below, then select all the reasons why we use scientific models. a models are always expensive. b models help you understand complex systems. c models allow exploring very small or very large systems. d models are used when systems are too expensive, expansive or impossible to use.

Explanation:

Scientific models simplify complex systems (b), enable exploration of extreme-scale systems (c), and substitute for impractical/expensive real systems (d). "Always expensive" (a) is false as models often reduce costs.

Answer:

B. Models help you understand complex systems., C. Models allow exploring very small or very large systems., D. Models are used when systems are too expensive, expansive or impossible to use.