A student sets up an experiment to measure the rate of oxygen production of an aquatic plant when it is photosynthesising. The student repeated the experiment several times to calculate the average amount of gas collected. Which two factors should be keep constant during the student's experiment?* (1 Point) 1. The size of the funnel and beaker
2.The size of the aquatic plant and the amount of gas in the measuring cylinder 3.The size of the aquatic plant and the time exposed to light
4.The size of the aquatic plant and the amount of water in the beaker

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