A combination of 0.250 kg of water at 20*C, 0.400 kg of aluminum at 26.0*C, and 0.100 kg of copper at 100*C is mixed in an insulated container and allowed to come to thermal equilibrium. Ignore any energy transfer to or from the container and determine the final temperature of the mixture. I know to use Q=mc(delta)T and that the energy lost should equal the energy gained, but how do I set up the equation for problems like this? One of the things that I don't know how to figure out is whether the aluminum will be losing energy to the water or gaining it from the copper. So I don't know how to set this up. Thanks.