65 grams of water at 70C are mixed with an equal amount of water at 30C in a completely insulated container. The nal temperature of the water is 50C. (a) How much heat is lost by the hot water? |:| cal [magnitude only) (b) How much heat is gained by the cold water'? |:| cal [magnitude only) (c) what happens to the total amount of internal energy of the system? 0 remains unchanged 0 halves 0 doubles