A solution of amphetamine (C₉H₁₃N) in dimethylsulfoxide (C₂H₆OS) has a molarity of 0.380 M. Given the density of solution is 1.12 g/mL, calculate the mass percent of carbon amphetamine in the solution (to three significant figures).

Given the K_b for water = 0.51 Ckg/mol, calculate the molar mass of an electrolyte with Van't Hoff factor = 4, if when 47.3 g of the solid is dissolved in 10.2 g of water the solution is measured to boil at 106.5 C.