09.29: The diagram to the right shows the lowest four ener
ix(p0 6pazz0epc;g r ,gy levels for an electron in a hypothetic
pp 0 xrz ecz60,(i;pgaal atom. The electron is excited to the -1 eV level of the atom and transitions to the lowest energy state by emitting only two photons. Which of the following energies could not belong to either of the photons?