Which of the following do not require a medium for transmission?

$A$ light wave traveling in air along the $x$-direction is given by $E_{y} = 540 \sin \pi \times 10^{4}(x - ct) \text{ Vm}^{-1}$. Then,the peak value of the magnetic field of the wave will be $\dots \times 10^{-7} \text{ T}$ (Given $c = 3 \times 10^{8} \text{ ms}^{-1}$)

Select the correct statement from the following:

The rms value of the electric field of an electromagnetic wave emitted by a source is $660 \ NC^{-1}$. The average energy density of the electromagnetic wave is

$A$ plane electromagnetic wave in a non-magnetic dielectric medium is given by $\vec{E} = \vec{E}_0 \sin(4 \times 10^7 x - 50t)$,where distance is in meters and time is in seconds. The dielectric constant of the medium is:

The average value of electric energy density in an electromagnetic wave is: