A mass spectrometer is being used to monitor air pollutants. It is difficult, however, to separate molecules

Question:

A mass spectrometer is being used to monitor air pollutants. It is difficult, however, to separate molecules with nearly equal mass such as CO (28.0106u) and N2 (28.0134u). How large a radius of curvature must a spectrometer have if these two molecules are to be separated on the film by 0.50mm?