Explain how the water in canals and irrigation ditches was controlled so that farmers could use it. (site 1)

This answer is correct i got 100%

Explanation:

The two-tier ditch uses plants and microbes to trap soil and nutrients, keeping them out of the runoff water. The ditch also slows down the water flow. Overall, the water that leaves the two-tier ditch is cleaner than water from a standard ditch.Farming in arid and semi-arid climates is challenging. There’s no way a farmer can rely only on rainfall to water crops—there simply isn’t enough rain. Therefore, farmers must bring water to the crops. At first, ancient peoples would just carry water in buckets to water their fields. But this was time-consuming and hard work. Eventually they figured out that irrigation was more effective.

velocity and height

the answer is c because it is most logical.