<span>The one topical reason for the plague portrayed by ibn khaldun which visited eurasia between the time period of 1331 and 1347 is that the rats, bugs, microbes, military clash in Caffa, as well as financial exchange or economic trade interfaces between Afro-Eurasia.
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The irrigation systems helped to water crops in large fields and make sure rivers don't overflow or [under-flow]<span />
Answer:
<u>Peristalsis:</u>
Peristalsis is the wave-like contraction of muscles of alimentary canal to enable the food to pass through the digestive tract.
<u>Place of Occurrence:</u>
Digestive Tract/Alimentary Canal
![\rule[225]{225}{2}](https://tex.z-dn.net/?f=%5Crule%5B225%5D%7B225%7D%7B2%7D)
Hope this helped!
<h3>~AH1807</h3>