Answer:
All organisms that have life, both plants and animals.
Explanation:
You didn't provide an illustration, but I guess I can still help. Biotic factor means that it has life, abiotic means it's not alive (hence the a- at the beginning.) Some biotic factors of a pond ecosystem include: earthworms, fishes, frogs, plants and insects.
30% of the earth's surface is covered by forests.
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The answer is B: Sister chromatid