If a vertical cilindo water (or any other liquid revolves around the self axis, as shown, the surface forms a smooth curve. Whereas water rotate as a unit (All with the same speed W), the shape of the liquid surface is a parabola described by the equation:

A) y = (W / g) r
B) y = 2 (W / g) r
C) y = 2 (W / g) r - r
D) y = (W / wg) r
E) = y (W / g) r-r

The question is this. Will someone please give me a light on how to solve this exercise? Make detailed!

Thanks

W is the angular velocity.