The density decreases because you are coming closer to the atmosphere and away from the center of the earth
The answer is B. It is the only one where each element has the same number of molecules on each side.
10 raise to 4 multiple by 1.8 is the answer
An indicator species<span> is an organism whose presence, absence or abundance reflects a specific environmental condition. </span>Indicator species<span> can signal a change in the biological condition of a particular ecosystem, and thus may be used as a proxy to diagnose the health of an ecosystem.
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