Answer:
1, to strengthen the bone
2, I would say it causes them to tense up (contract)
Aorta!
Hope this helps! :)
<span>Explanation: Oxygen is the more electro-negative of the atoms in the water molecule, so it tends to pull the 'shared' electron more to itself. Thus, the oxygen atom has a greater time-share of all electrons, and therefore the hydrogen atoms are more positive for a partial lack of electrons</span>
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