15. A 5.86-gram sample of a compound is dissolved in 250. grams of benzene. The freezing point of this solution is 1.02°C below that of pure benzene. What is the molar mass of this compound? (Note: Kf for benzene = 5.12°C/m.) Ignore significant figures for this problem. (A) 29.4 g/mol (B) 118 g/mol (C) 235 g/mol (D) 4.67 g/mol (E) 58.8 g/mol