system
Given the following post, respond as if you're commenting on Reddit:
human
If you took 100 liters of water at 80 degrees and mixed it with 100 liters of water at 60 degrees, would you get 200 liters of 70 degree water?
gpt
Yes, approximately. 

You're broadly interested in the heat capacity of water - it tells you how much energy you need to change the temperature of water. While in most real systems the heat capacity does have some small variation with temperature, it can generally be taken to be constant, especially over a small range of temperatures like the problem given here. In this case, assuming constant heat capacity for water and no evaporative or cooling losses, you will end up with 200 L at 70 degrees.