How Do You Calculate Hydrostatic Forces on a Sloped Seafloor Wall?

[chimmy48]

Homework Statement

a) Determine the horizontal and vertical forces acting on a wall sloped at angle, θ, to the horizontal seafloor as a function of z. Assume that the water is h deep and that atmospheric pressure acts everywhere. b) Determine the total resulting force and center of pressure.

Homework Equations

I really don't know what to use. Let's see:
F = P_cg*A = (P_a + pgh_cg)A, where P_cg is the pressure at centre of gravity, P_a is the atmospheric pressure

The Attempt at a Solution

I really don't know how to approach this question, that's why I'm asking for help.

 

[Astronuc]

Do you have a picture? Is this a seawall (sea on one side/air on the other), or is it a submerged wall?