Answer:
I thinks it's B
Explanation:
Because it's what dams do.
It's not D because it caused people to relocate, it's not C because that doesn't make sense.
1-choose any two points on the line.
2-draw a right-angled triangle with the line as hypotenuse.
3-use the scale on each axis to find the triangle's: vertical length.horizontal length.
4-work out the vertical length ÷ horizontal length.
5-the result is the gradient of the line.
