Easy. Answer is oxygen because it says which one was missing before any life was on earth. And in order to have life on earth you need oxygen!
:)
ʜᴇʟʟᴏ ᴛʜᴇʀᴇ!
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In the rock cycle, sediment is stripped away and transported by the process of erosion after the process of weathering has taken place.
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нσρє тнιѕ нєℓρѕ уσυ!.
gσσ∂ ℓυ¢к :).
нανє α gяєαт ∂αу.
- нαηηαн ❤.
Hello,
Here is your answer:
Your answer is the circulatory system!
The circulatory system connects the veins all around the body so the blood can be transported around the body.
Your answer is Circulatory system!
If you need anymore help just ask me!
Hope this helps!
<h3> Answer</h3>
alveoli
<h2> Explanation</h2>
During gas exchange oxygen moves from the lungs to the bloodstream. ... This happens in the lungs between the alveoli and a network of tiny blood vessels called capillaries, which are located in the walls of the alveoli.
