circle wiki:
>This article is about the shape and mathematical concept of circle; for other meanings, see Circle (disambiguation). In Euclidean geometry, a circle is the set of all points at a fixed distance, called the radius, from a fixed point, called the centre (center). The points can only be those that are part of a conic section; within the set of a plane bisecting a cone. Circles are simple closed curves, dividing the plane into an interior and exterior. Sometimes the word circle is used to mean the interior, with the circle itself called the circumference. Usually however, the circumference means the length of the circle, and the interior of the circle is called a disk or disc.
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green wiki:
>For other uses, see Green (disambiguation). Green is a color seen commonly in nature. Many plants are green mainly because of a complex chemical known as chlorophyll which is involved in photosynthesis.Green light has a wavelength of roughly 520â570 nm and is one of the additive primary colors. It is the complement of magenta. Many artists, however, continue to use a traditional color theory in which the complement of green is considered to be red.People who are red-green color blind can often distinguish between the two colors but confuse them with other colors, for example, bright green with yellow; dark green with brown.
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