A 42.10 g piece of copper (molar heat capacity of 24.47 J/ C*mol) is heated to 78.0 deg. C and dropped into a calorimeter containing water (specific heat capacity 4.18 J/ g C) initially at 20.2deg C. The final temperature of the water is 33.7 deg C. Caluclate the mass of water in the calorimeter.