The mass spectrum of this compound shows a molecular ion at m/z = 113, the IR spectrum has characteristic absorptions at 2270 and 1735 cm?1, and the 13C NMR spectrum has five signals. A) Based on the mass spectral data and the IR data, what functional groups are present in this compound? B) How many types of nonequivalent protons are there in this molecule? C) Describe the signal at 3.5 ? in terms of its integration, splitting pattern and chemical shift.