A plane Electro magnetic wave of frequency $30\; MHZ$ travels in free space component of wave at a point $E= 6V/m$ along y direction . The magnetic field component B at this point would be

Question

$(a)\;2 \times 10^{-8}\;T\;along\;z\;direction\\ (b)\;6 \times 10^{-8}\;T\;along\;x\;direction \\(c)\;2 \times 10^{-8}\;T\;along\;y\;direction\\(d)\;6 \times 10^{-8}\;T\;along\;z\;direction $