Answer:
The Amazon is the world's longest river.
The Mississippi, Missouri, Tennessee, and the Ohio River
It's being estimated that dinosaurs lived on Earth from about 237 million years ago to about 66 million years ago. So answers B and D are definately too "old", while answer A is too "young". I'd pick answer C as it's most probable.
Investigate past climate and atmospheric changes
The scientific method is a method of investigation involving experimentation and observation to acquire new knowledge, solve problems, and answer questions. The key steps in the scientific method include the following: Step 1: Make observations. Step 2: Formulate a hypothesis.
hOpe it helps
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