A conical tank with a bottom opening of cross-sectional area A is filled with water and is mounted on supports as shown in the figure. What is the force F with which plate X must be pushed up to prevent water from leaking ? Assume that the density of air is negligible as compared to the density of water ρL.

• A. ρL . Vg
• B. ρL . A.Hg
• C. ρL . Vg/2
• D. ρL .Vg/3