A 0.1 molal aqueous solution of a weak acid is 30% ionized. If Kf for water is 1.86oC/m, the freezing point of the solution will be

Question

A 0.1 molal aqueous solution of a weak acid is 30% ionized. If K_f for water is 1.86^oC/m, the freezing point of the solution will be

$-$0.18^oC