A plane electromagnetic wave of frequency 50 MHz travels in free space along the positive x-direction. At a particular point in space and time, $\vec{\text{E}} = 6.3\hat{\text{j}}\text{V/m}$. The corresponding magnetic field $\vec{\text{B}}$, at that point will be:

(1) 18.9x10^{-8} $\hat{\text{k}}$T

(2) 6.3x10^{-8} $\hat{\text{k}}$T

(3) 2.1x10^{-8} $\hat{\text{k}}$T

(4) 18.9x10^{8} $\hat{\text{k}}$T