Answer:
815.59
Step-by-step explanation:
Assuming no heat lost to the Surrounding
Total heat lost by granite = Total heat gained by water
mc∆T of granite = mc∆T of water
m x 0.79 x (54.1 - 29.2) = 467.62 x 4.184 x (29.2 - 21.0)
m x 19.671 = 16043.48106
m = 16043.48106/19.671
= 815.59J