Degrees
There are 100 gradians (gons) in a right angle. 1 gradian of arc = 100km at the equator. The unit was originally defined by French artillerymen and subsequently taken up by surveyors.
1/36th of a circle. This unit was used by ancient Egyptians, which divided the circle of the Zodiac into 36 divisions. The unit is still used sometimes in astrology, where one dekan equals 1/3 sign.
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