A Blacksmith Drops a 550 ^$\circ$ F Piece of Iron into a Vat of 75

A blacksmith drops a 550 ^$\circ$ F piece of iron into a vat of 75 ^$\circ$ F water in order to cool it to 100 ^$\circ$ F.How many kilograms of water are needed per kilogram of iron? Assume all the thermal energy from the iron is transferred to the water and none of the water evaporates.The specific heats of water and iron are 4186 J/kg ^$\circ$ C and 448 J/kg ^$\circ$ C,respectively.

A) 9.3 kg
B) 0.78 kg
C) 0.52 kg
D) 1.9 kg