9.A conical funnel of half-angle 0 is filled to some initial height ho with a fluid. At time t = 0 the drain plug is removed and the fluid drains

through a hole (with area a) in the bottom of the funnel.Assume that the drain hole area is small compared to the fluid surface area. b) Find an expression for the fluid height h(t) as a function of time. c) Find an expression for the funnel drain time.