What is the value of the speed of light in free space?

$A$ plane electromagnetic wave of frequency $25 \text{ MHz}$ travels in free space along the $X$-direction. At a particular point in space and time,the magnetic field is $\overrightarrow{B} = 2.1 \times 10^{-8} \hat{k} \text{ T}$. Find the electric field $\overrightarrow{E}$ at this point.

An electromagnetic wave with frequency $\omega$ and wavelength $\lambda$ travels in the $+y$ direction. Its magnetic field is along the $+x$ axis. The vector equation for the associated electric field (of amplitude $E_0$) is:

$A$ plane electromagnetic wave having a frequency $n = 23.9\, GHz$ propagates along the positive $z-$ direction in free space. The peak value of the electric field is $60\, V/m$. Which among the following is the acceptable magnetic field component in the electromagnetic wave?

For a plane electromagnetic wave propagating in the $x$-direction,which one of the following combinations gives the correct possible directions for the electric field $(E)$ and magnetic field $(B)$ respectively?

The vectors $\vec{E}$ and $\vec{B}$ of an electromagnetic wave in vacuum are