So, now, we just use the pressure expression and then substitute in this equation to obtain the F of x into F suffix x k. So, I get the force acting in the horizontal direction, which is now going to be a function of water depth. So, which is going to be a function of water depth of course, it is going to be a function of wave height, water depth and it is going to vary with respect to frequency which is brought into k and sin of k a will be a constant. Now, this going this will give the variation of the force and the phase variation of the force. Is that clear?