Treatment of molecule a with mg forms a grignard reagent that reacts with ch2═o to form h after water is added to the reaction mixture. h has a molecular ion in its mass spectrum at m/z = 86, and shows fragments at 71 and 68. h exhibits absorptions in its ir spectrum at 3600−3200 and 1651 cm−1, and has the 1h nmr spectrum given below. draw the structure of h.