(a) An excited hydrogen atom emits a photon with a frequency of 1.1411014Hz to reach a state with n=4. What was the value of n for the state in which the electron originated? Given the following: En=RH(n2Z2), where Z is the nuclear charge, n is the principal quantum number and RH=2.1791018J. (3 marks) (b) The series in the He+spectrum that corresponds to the set of transitions where the electron falls from a higher level to a state with n=4 is called the Pickering series. Using the equation given in (a), calculate the wavelengths of the first three lines of this series. In what region(s) of the spectrum do these transitions occur? (8 marks) (c) Explain the physical significance of the energy state characterized by n= and E=0 for a hydrogen atom. (2 marks)