Calculate the rate of photosynthesis (mm/hr) for Elodea if when measuring net photosynthesis, the water level moved up 3 mm from the initial level in 20 min, and when measuring cellular respiration it...

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Extracted text: Calculate the rate of photosynthesis (mm/hr) for Elodea if when measuring net photosynthesis, the water level moved up 3 mm from the initial level in 20 min, and when measuring cellular respiration it took 15 minutes for the water level to move down 1 mm.