Respuesta :

The relationship between photon frequency and photon energy is given by the relation E=hf. Here E is the photon energy, f is the photon frequency and h is the Planck constant. Thus, by rearranging this equation we find that the frequency of a photon with energy 1.99 x10^-19 Joules is 300330000 Mega-Hertz. 
It's 3.00 x 10^14 Hz