Hey guys, we will never decide what is correct answer without showing how it was derived.

Check the following.

V = Pi*r^2*h/3 (Cone volume in terms of height & radius).

For cone in question, r = 5*h/8

Hence V = Pi*(5*h/8)^2*h/3

or V = 25*Pi*h^3/192

dV = (25*Pi*h^2/64)*dh

dV = (25*Pi*16/64)*dh

dV = (25*Pi/4)*dh

.1 = (19.635)*dh

dh = .1/19.635

dh = .00509 meters/second

I did not recheck all of the above. If you disagree, show me my error. There might be one.