$3-$ In lossless medium with $=3=3,$ an electromagnetic plane wave of the electric field is: $()=6+36$ f$-$ Determine the wavenumber $($k$),$ frequency $(),$ wavelength $(),$ phase velocity $(),$ intrinsic impedance $(),$ unit propagation direction $()$ of plane wave. g$-$ Determine the $$ constant for $<0,$ if electromagnetic plane wave has circular polarization. h$-$ Find the poynting vector of plane wave by using results of section $($b$)$ i$-$ Find the average power density of propagating wave.