Question

give me breif solution as early as possible​

Answer 1

Answer:

I hope you understand...

Answer 2

Answer:

volume of well=volume of embankment (ring)

πr²h=πh(R²-r²)

after cancelling π

r²h=h(R+r)(R-r)

7*7*12=h*21*7   [R+r is 21 as it the total radius of ring which is (radius of                             well (14)+ width of the ring )+ the small radius of the well and R-r is 7 as it is the width or difference between the two radii]

=>h=7*7*12/21*7

on cancelling terms we get h=4

hope it helps.....