Answer: The graph shows that chlorophyll a absorbs light principally around 420-450 nm and 650-680nm wavelengths
Explanation: Chlorophyll a is a pigment found in plants that traps light energy for use in photosynthesis. Chlorophyll a absorbs light mostly in the blue and orange-red wavelengths. This is shown in the graph, where the peaks are around the 400nm and 600nm wavelengths, corresponding to blue and red in visible light.
This absorption means the pigment is 'excited' by this light, sending into a higher state if energy which provides energy for the reactions of photosynthesis.