Answer: you ask questions to determine relationships, including quantitative relationships, between independent and dependent variables. Ask questions to clarify and refine a model, an explanation, or an engineering problem. Evaluate a question to determine if it is testable and relevant.
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If it has valves then it is a vein.
A way scientist answer questions and solve problems
Answer:
Food webs and food chains.
A food web describes the flow of energy and nutrients through an ecosystem, while a food chain is a linear path through a food web
