1) easily recognizable
2) wide geographical distribution
3) abundant
4) existed for a short period of time
<u>ANSWER:</u>
Artificial levees are 'earthen mounds' built on the river banks to increase the 'volume of water' the channel can hold.
<u>EXPLANATION:</u>
- A levee or stop bank is called as a 'natural or artificial wall' or a bank which is used to protect the flooded water in a certain area and these Levees are made from the compact earth.
- There are two type of levee, artificial and natural. Artificial levee often seems to get damaged which may cause breach.
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