09.29: The diagram to the right shows the lowest four ener
+k)wdk9yu g6km f r::qr vtl90gy levels for an electron in a hypo
fvr k kgqwr :+mt)dy09 9kl:u6thetical 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?