An experiment is set up to investigate the effect of light intensity on the rate of photosynthesis in Elodea. Initially, the light source is placed at a distance of 25 cm from the plant, and the light intensity is recorded as 180 arbitrary units180\text{ arbitrary units}180 arbitrary units.
The light source is then moved to a distance of 75 cm from the plant. What is the new light intensity received by the plant?
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