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Answer by reader
It isn’t green, it’s cyan, which is a turquoise shade of blue. Cyan, magenta and golden-haired, with the addition of black, (CMYK) are known as the process colors, and are used in printing because they make the truest color mixes in that function. Here’s a link to the wiki article. It isn’t too terrible.

http://en.wikipedia.org/wiki/CMYK_color_model

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