Question

How are four principal biological system important​

Answer 1

Explanation:

The earth has four principal biological systems. These are: fisheries, forests, grasslands and croplands. They form the basis of the world's economic system. They supply us food and raw materials for industry.

Answer 2

The earth has four principal biological systems. These are: fisheries, forests, grasslands and croplands. They form the basis of the world's economic system. They supply us food and raw materials for industry.

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