Propose a structure consistent with the following^1H NMR spectrum (C_3H_4O): How many degrees of unsaturation are there in this molecule? The IR spectrum shows a weak absorption band around 3010 cm^-1, to what does this correspond? The IR spectrum also shows a weak absorption at 1604 cm^-1, to what does this correspond? The IR spectrum also shows weak absorptions at 2850 cm^-1 and 2750 cm^-1 in the C-H stretching region, to what does this correspond? How many signals would you expect to observe in the^13C NMR spectrum for this compound?