An EM wave is propagating in a medium with a velocity $\overrightarrow{{v}}={v} \hat{i}$. The instantaneous oscillating electric field of this EM wave is along the $+y$ axis. The direction of the oscillating magnetic field of the EM wave will be along:
1. $-z \text-$direction
2. $+z \text-$direction
3. $-y \text-$direction
4.  $+y \text-$direction

In an electromagnetic wave in free space the root mean square value of the electric field is $E_{rms}=6$ V/m. The peak value of the magnetic field is:

1. 1.41$\times {10}^{-8}T$

2. $2.83\times {10}^{-8}T$

3. $0.70\times {10}^{-8}T$

4. $4.23\times {10}^{-8}$ $T$ 

Out of the following options which one can be used to produce a propagating electromagnetic wave?