1.what is the purpose of each of the five parts of the mass

1.what is the purpose of each of the five parts of the mass spectrometer?
2.if hydrogen has only one electron,how can it have five lines in its line emission spectra?
3.a）evidence for the existence of energy levels in atoms is provided by line spectra.state how a line spectrum differs from a continuous spectrum
b)on the diagram below draw four lines in the visible line spectrum of hydrogen
c)explain how the formation of lines indicates the presence of energy levels