Commercial grades of stearic acid(C17H35COOH) usually contain some palmiticacid (C15H31COOH) as well. A 1.115-g sample of a commercial -grade stearic acid is dissolved in 50.00 mLbenzene (d = 0.879 g/mL), and the freezing point of the solution is found to be 5.072 oC. The freezing point of pure benzene is 5.533 oC. What is the approximate mass percent palmitic acid in the stearic acid?