Finding a surface area of a face using macro code

Hi everyone, I am planning to create a macro code for measuring a surface area of a face. I managed to write the code for choosing a face, but I cant figure out a code for measuring the surface area of that face. Do let me know how I can do this. I have attached the code for choosing a face of the part body as well as the model file. Much appreciated

SolidworksApi/macros