Read the following paragraph and answer the question. Give ONLY the answer, no other words or explanation.

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Answer: <most likely answer, as short as possible>.

Paragraph: 
Materials that eject electrons when illuminated with light, such as potassium, are called photoemissive. Not all materials are photoemissive, nor are all light sources capable of initiating electron emission from a given substance. For example, in Figure above , we see that 700 nm light will not initiate electron ejection, while 550 nm light will.


Question: What are materials that eject electrons when illuminated with light called?
photoemissive
Photoemissive materials.