Answer:
10 units
Explanation:
Each organism that the energy has to got through leaves only 10% of the energy that they got. So for each organism that consumes the energy, there is only 10% left for the next organism that consumes it. Tertiary consumers are level 4, so you have to take 10% of 100,000 4 times to get the answer 10 units of energy is left.
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