125.0 g of an unknown substance is heated to 97.0°C. It is then placed in a calorimeter than contains 250g of water with an initial temperature of 20.0°C.
The final temperature reached by the calorimeter is 23.5°C.
What is the specific heat of the unknown substance? The specific heat of water is 4.18 J/ (°C × g)

A) 0.285 J/ (°C × g)
B) 0.398 J/ (°C × g)
C) 0.729 J/ (°C × g)
D) 1.24 J/ (°C × g)