Triple tanks You decide to have a more elaborate setup and connect three small fish tanks in a loop. You run pipes from tank C to tank D, from tank D to tank E, and finally from tank E back to tank C. Pumps are installed so that water is constantly cycling through all three pipes at the rate of 1 litre per minute. Suppose initally tank C is filled with 40 litres of salt water with a concentration 80 grams per litre, tank D with 20 litres of fresh water, and tank E40 litres of fresh water
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