|≈||approximately equal to|
|digits||indicates that digits repeat infinitely (e.g. 8.294 369 corresponds to 8.294 369 369 369 369 …)|
The gradian is a unit of measurement of an angle, equivalent to 1/400 of a turn, 9/10 of a degree, or π/200 of a radian.
1/2 circle or half circle is equal to 360°/2 = 180°. Plural name is helf circles.
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