a) An electron is initially in the = 2 state of a 1D infinite quantum well with width = 2 nm and undergoes an optical transition to the = 1 state by emitting a photon. What is the energy of the emitted photon? b) A Hydrogen atom is placed in a magnetic field B = Bz B with = 3 T. What is the energy splitting between the ml = 0 and the ml = 1 states? c) Estimate the probability that an electron with energy equal to E = 2 eV will pass though a barrier with a height of V0 = 4 eV and a width of 6 .