The Freezing Point of Seawater Is About -1 $\omicron$ C If Seawater Is an Aqueous Solution of Sodium Chloride,Calculate the C

The freezing point of seawater is about -1.85 ^$\omicron$ C .If seawater is an aqueous solution of sodium chloride,Calculate the molality of seawater.The k_f for water is 1.86 K/m.

A) 1.99 m
B) 0.995 m
C) 3.44 m
D) 3.70 m
E) 0.497 m