How many marks would I get for
In the beaker, measure out a set amount of water, and place the pondweed into this container. Using the ruler, measure a set distance between the beaker and the lamp. After regular intervals, measure how much water remains (the less water remaining the more the plant has photosynthesised). Repeat these steps increasig the distance between the light and the beaker. In the investigation you would have to control the starting amount of water, use the same light bulb, and leave the plant in the water for regular and consistent intervals.
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