Pure Liquid $A$ is stored in a cylindrical container with a diameter of $D$ and a height of $H.$ Gas $B$ flows parallel to the top of this container. Moreover, gas $B$ does not dissolve into liquid $A.$ Liquid A starts to vaporize into gas space above the liquid surface. The liquid has been added into this container to maintain the liquid level constant at $Z_1.$ The diffusion coefficient of $A$

diffused through gas $B$ is $D_{AB}.$ Determine the flux of A diffused through $B.$Also, derive the concentration profile equation of component $A$ in the gas phase.