What are the equations that represent how the energy of an electromagnetic wave is related to the frequency of the wave and to the wavelength of the wave? define h and c in your equations and give their values.

The equation that represents how the energy of an electromagnetic wave is related to the frequency of the wave and to the wavelength of the wave is known as the Planck - Einstein equation.

Such equation states that the energy of a photon of light (electromagnetic radiation) is proportional to its frequency:

Where:

Since the frequency and the wavelength are inversely related as per the equation λ = c / f, where λ is the wavelength and c is the speed of light, you can derive the equation that relates the energy of an electromagnetic wave with the wavelength:

Where  λ is the wavelength and c is the speed of light.

The value of c in vacuum is a constant and is equal to 299,792,458 m/s m/s, which is usually approximated to 3.0 × 10⁸ m/s

the answer is definitely c.