It’s a quantum mechanics problem, hope somebody could help me.

The spacing between vibration levels of the CO molecule is 2170 cm‘1 when the carbon and oxygenatoms are of the common stable isotopes 120 and 160, respectively. a) From this, compute the effective spring constant of the molecular potential V(‘r) (r is thedistance between the carbon and oxygen nuclei). Hint: you will have to consider the reducedmass ,u = M1M2 / (M1 + M2) where M1 and M2 are the masses of the two nuclei. Also, recall thespectroscopic convention that energies are given in terms of the wavenumber k (in units cm‘l) ofa photon with energy E = Tick. b) If I change the carbon atom to the isotope 13C while molecular potential V(‘r) remains the same,what’s the spacing between vibration levels in cm‘l?