Answer:
<u>A common element among all the river valley civilizations was irrigation systems that moved water to crops and settlements</u>
Explanation:
- <u>River Valley civilizations where the civilizations that were found on the banks of the river like the Mesopotamia ,Indus valley civilization.</u>
- <u>These civilization where agriculture based civilization as they depended on river for drinking water and irrigational activities</u>
Answer: "homeostasis" .
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Answer: Energy decreases as it moves up trophic levels because energy is lost as metabolic heat when the organisms from one trophic level are consumed by organisms from the next level. Trophic level transfer efficiency (TLTE) measures the amount of energy that is transferred between trophic levels. or in materials that the consumer does not digest, or through movement
Hope it helps! ^w^