[" Q4.In a plane electromagnetic wave,the "],[" electric field oscillates sinusoidally at a "],[" frequency of "2.5times10^(10)Hz" and amplitude "],[480V/m" .The amplitude of the oscillating "],[" magnetic field will be "],[" (a) "1.52times10^(-8)Wb/m^(2)],[" (b) "1.52times10^(-7)Wb/m^(2)],[" (c) "1.6times10^(-6)Wb/m^(2)],[" (d) "1.6times10^(-7)Wb/m^(2)]