$1.(35$ points$)$ Given: The electric field in free space, in spherical coords:

E$($R$,,$t$)=$ sin$$ cos$[(18\mathrm{.}85$X$108$ rad$/$sec$)$t $-6\mathrm{.}28$R$]$ V$/$m

$^0\mathrm{.}02$

$$

Using the time$-$harmonic Maxwell's equations with phasor E and H$,$ Find: H$($R$,,$t$)$