Explain the method to measure the external diameter of a sphere

The sphere is that the circular objects in the two-dimensional space (1) circle

(2) disk. Two-dimensional space is a set of points and the distance of that point, The two points of Sphere that length and center.

The sphere can be constructed as the name of surface form circle about any diameter. The circle is the special type of the revolution replacing the circle,

the sphere is the distance r is the radius of the ball and the circle is the center of the mathematical ball, as the center and the radius of the sphere is to respectively.

The ball and sphere have not to be maintained mathematical references as solid references. A sphere of any radius is centered at the number of zero.

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