(a) Write the point-form of Maxwell's equations in the frequency domain for an air-filled rectangular waveguide. (b) Derive the vector wave equation in terms of the frequency-domain electric field intensity (c) Derive the scalar wave equation in term of H,. Also derive a simplified second order partial differential equation in terms of H, with the axial variation of the wave of e-iPo. (d) Write the H, expression in the dominant mode.