Give the structural formulas of compounds A, B, and C in the following problems. EXPLAIN EXACTLY HOW YOU ARRIVED AT EACH ANSWER.
Compound A is a water-soluble liquid that gives positive 2,4- dinitrophenylhydrazine and iodoform tests and a negative Tollensâ€^TM test. The IR spectrum of A has bands at 2950, 1720 and 1370 cm-1. The 1H NMR spectrum consists of four signals: a triplet at ï¤ 2.3, a singlet at ï¤ 2.0, a sextet at ï¤1.3 and a triplet at ï¤ 1.2. in a ratio of 2:3:2:3 respectively.

Compound B is a liquid that is insoluble in water but soluble in 5% HCl. The 13C NMR spectrum of B consists of four signals in the ï¤ 100-140 region (DEPT indicates CH, CH, CH and C) and another signal at ï¤ï€ 55 (DEPT indicates CH3). The IR spectrum of B has bands at 3410, 1600 and 1500 cm-1 but none at 1620-1680 cm-1.

Compound C, molecular weight 118, is soluble in water to give a solution with a pH of 3. A 0.330-gram sample of C requires 27.9 mL of 0.200 M NaOH to reach the end point in a titration. The 1H NMR spectrum of C consists of the following signals: Splitting ï¤ Relative Area a singlet 13.1 2 b quartet 3.6 1 c doublet 1.8 3