Consider the following energy levels of a hypothetical atom: E4-2.51 x 10-19 J Ez-5.01 x 10-19 J E2-1.35 x 10-18 ] E, -1.45 x 10-18 (a) What is the wavelength of the photon needed to excite an electron from E, to E/? x 10 m (6) What is the energy in joules) a photon must have in order to excite an electron from E, to Ez? x 10 J (c) When an electron drops from the E, level to the E, level, the atom is said to undergo emission. Calculate the wavelength of the photon emitted in this process. x 10 m