Need help on energy equasions please!! question, released, problem

amy

1. The problem statement, all variables and given/known data
I need help on this homework question please i dont know how to solve it2. Relevant equations
how many calories of heat are released by 25 g of water as it drops in temperature from 77 degrees c to 50 degrees c ( 1 cal= 4.18)3. The attempt at a solution

I dont know which equasion i should use
Q= cmDeltaT ?  

    try it.