Answer:
its a or b most likely a tho
Explanation:
Explanation: Rivalry
There is safety in numbers, and with that, they can run together more often without the fear of being attacked, and must push themselves to match others, therefor getting fit
Answer: change in solar output.
The wall of the heart<span> consists of three </span>layers<span>: the epicardium (external </span>layer<span>), the myocardium (middle </span>layer<span>) and the endocardium (inner </span>layer<span>). The epicardium is the thin, transparent </span>outer layer<span> of the wall and is composed of delicate connective tissue.
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