The average value of electric energy density in an electromagnetic wave is. [where $E_0$ is peak value]

The electric field component of a monochromatic radiation is given by
$\vec E = 2E_0 \hat i \cos kz \cos \omega t$
Its magnetic field $\vec B$ is then given by

The amplitude of the magnetic field part of a harmonic electromagnetic wave in vacuum is $B_0 = 510 \; nT$. What is the amplitude of the electric field (in $N/C$) part of the wave?

The electric field component of an electromagnetic wave in vacuum is given as $\vec E = 3\cos(1.8y + 5.4 \times 10^8 t)\hat i$. Its direction of propagation and wavelength are:

Identify the correct statements from the following descriptions of various properties of electromagnetic waves.
$A$. In a plane electromagnetic wave,the electric field and magnetic field must be perpendicular to each other,and the direction of propagation of the wave should be along the electric field or magnetic field.
$B$. The energy in an electromagnetic wave is divided equally between the electric and magnetic fields.
$C$. Both the electric field and magnetic field are parallel to each other and perpendicular to the direction of propagation of the wave.
$D$. The electric field,magnetic field,and direction of propagation of the wave must be mutually perpendicular to each other.
$E$. The ratio of the amplitude of the magnetic field $(B_0)$ to the amplitude of the electric field $(E_0)$ is equal to the reciprocal of the speed of light $(1/c)$.
Choose the most appropriate answer from the options given below:

In an $EM$ wave,the amplitude of the magnetic field $H_0$ and the amplitude of the electric field $E_0$ at any place are related as: