The magnetic field of a plane electromagnetic wave is given by → B...

The ratio of electric field amplitude to the magnetic field amplitude of an electromagnetic wave is equal to the speed of light in the medium. Therefore,

$c = \dfrac{{E}_{0}}{{B}_{0}} ⇒ {E}_{0} = c{B}_{0}$

$⇒ {E}_{0} = 3 \times {10}^{8} \times 2 \times {10}^{- 8}$

$⇒ {E}_{0} = 6V{m}^{- 1}$

According to the given equation $\overset{\to}{B} = 2 \times {10}^{- 8}sin$\left(0 . 5 \times {10}^{3}x + 1 . 5 \times {10}^{11}t\right)\overset{^}{j}T$the wave travels in$x$direction. As electric field and magnetic field vibrate perpendicular to the velocity of light, electric field can not be along$x axis.