Is water because a fish in order to survive it needs water
18 valance electrons, Hope this helps!
Is constant (matter that has a composition that is the same everywhere)
The answer iiiis... A: Group 8A, Period 1
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Here's why:</h3>
The way I found this doesn't have much thought or explanation--I just remember that helium and hydrogen are in period 1. The only answer choice with "period 1" is A.
