How much time will it take for information to propagate over a distance of $30 \, km$ in space?

Which of the following statements are true?
$A.$ Speed of light in vacuum is dependent on the direction of propagation.
$B.$ Speed of light in a medium is independent of the wavelength of light.
$C.$ The speed of light is independent of the motion of the source.
$D.$ The speed of light in a medium is independent of intensity.
Choose the correct answer from the options given below:

The amplitude of the electric field associated with a light beam of intensity $\frac{15}{\pi} \text{ W m}^{-2}$ is (in $\text{ N C}^{-1}$)

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

In an $E.M.$ wave,the average energy density is associated with

In a plane electromagnetic wave,$U_E$ and $U_B$ are the average energy densities of the electric field and magnetic field,respectively. Then,which of the following is the correct option?