[EX5TASY]

i'm not quite sure what this problem is asking...

A 129 g sample of copper (specific heat capacity = 0.20 J °C-1 g-1) is heated to 87.3°C and then placed in a container of water at 22.3°C. The final temperature of the water and copper is 26.9°C. What is the mass of the water in the container, assuming that all the heat lost by the copper is gained by the water?

I know q(system) = -q(surroundings), but which temperatures are the ones that matter?

[EX5TASY]

nvm, i figured it out.. plz disregard