A 100-G Block of Copper Is Taken from a Kiln $\degree$

A 100-g block of copper is taken from a kiln and quickly placed into a beaker of negligible heat capacity containing 300 g of water. The water temperature rises from 15 $\degree$ C to 40 $\degree$ C. Given c_Cu = 0.10 cal/g· $\degree$ C, and c_water = 1.00 cal/g· $\degree$ C, what was the temperature of the kiln?

A) 500 $\degree$ C
B) 635 $\degree$ C
C) 790 $\degree$ C
D) 535 $\degree$ C