A plane wave in air with Eei $=($x$9$y$4$z$6)$e $$j$(2$x$+3$z$)($V$/$m$)$ is incident upon the planar surface of a dielectric material, with r $=2\mathrm{.}25,$ and it occupies the half$-$space z $0.$ Determine: $($a$)$ the incidence angle i $,($b$)$ the frequency of the wave, $($c$)$ the field Eer of the reflected wave, $($d$)$ the field Eet of the wave transmitted into the dielectric medium, and $($e$)$ the average power density carried by the wave into the dielectric medium.