Atoms. Every element is made of a specific type of atoms.
Answer:
D i think would be the best answer my studie in this part of health is low
The answer to your question is <span>B. Natural selection acted on the variation that was present in the population.
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Answer:
I think its A
Explanation:
Because the reason why airplane have closed windows is because we can't breathe in carbon dioxide when we go up. Of course there is oxygen just not a lot as we go up. Why would there be helium in the air? We would sound weird when we skydive.
The determining factors are; climate, environment, and Human Activity.
P.S.: try those...lmk if they are right ;)