Propose two different combinations of bonding features to account for an IHD of 5 in a molecule consisting of C and H atoms and one O atom only (i.e. C x H y O). For example, a molecule with molecular formula C x H y O and IHD = 2 may have one C=O bond and one ring (this is an example of one combination). For this exercise, do not propose more than one ring. C x H y O, IHD = 5, combination 1