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>
<span>Leptin. Leptin is produced by fat cells and released when your body has enough fat in storage. When leptin reaches the brain, it gives your body a feeling of fullness so that you will not want to continue eating.
Individuals with leptin resistance, where the leptin hormone signals are not received as they should be, are often overweight because they do not have the same brain signals telling them that their body is full.</span>
Carbon dioxide and oxygen cannot pass through but move in and out
D. i think if i get you wrong then I'm sorry
D.
Firstly light is an external stimuli. in plants - shoots are positively phototrophic while roots are negatively phototrophic.