$3.$ The magnetic field vector for a plane wave traveling in a non$-$magnetic lossless medium is as follows.

H$($x$,$ t$)=20$ cos$(2$$108$t $10$x$)$ ez

Accordingly, determine the following.

a$)$ Relative dielectric constant, $6.(5$p$)$

b$)$ Wavelength $($$)$ and phase velocity $($v$).(5$p$)$

c$)$ Wave impedance, $().(5$p$)$

d$)$ Polarization. $(5$p$)$