Q: In the presence of oxygen, hydrogen can interact to make what? Choices: - carbon - helium - acid - water A:
water
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Q: What do organisms use to store energy? Choices: - tissues - proteins - metabolytes - lipids A:
lipids
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Q: Secondary consumers are usually carnivores that eat what? Choices: - soil - plants - dead material - primary consumers A:
primary consumers
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Q: Approximately how many billion years ago did our solar system begin? Choices: - four billion - three billion - nine billion - five billion A:
five billion
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