If the primary producers produce 5000 energy units, about how much of this energy is available to the third-level consumers?

5 energy units

Explanation:

This is called the Ten-Percent rule! Every trophic level you go up, you only take 10% of the previous trophic level's energy!

Primary producers

5000 energy units (100% of 5000)

First-level Consumers

500 energy units (10% of 5000)

Second-level Consumers

50 energy units (1% of 5000)

Third-level Consumers

5 energy units (0.1% of 5000)

50 energy units that should be the answer

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