Final answer:
The primary colors for light addition are red, green, and blue, corresponding to the three types of cones in the human eye. Various combinations of these primary colors produce all different hues. If red and green lights shine on a white screen, the color perceived is yellow.
Step-by-step explanation:
The three primary colors for light addition are red, green, and blue. Each of these colors corresponds to a type of cone in the human eye, which is where we perceive colors. Various combinations of the primary colors produce all the hues we see. When light of only two primary colors is shone on a white screen, the color perceived is a mixture of the two. For instance, if red and green lights shine on a white screen, the color perceived is yellow, as this is the combination of red and green in the correct ratio of intensities.
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