According to Baidu Education, the cubic formula of a circle is the area multiplied by the height. To get the volume of a circle, its area and height are necessary conditions, and to get the area of a circle, you must know the radius of the circle.

On the plane, a circle is a set of points whose distance from a fixed point is equal to a fixed length, which is called a circle. A circle has countless symmetry axes, which pass through the center of the circle and are rotation invariant. A circle is a conic curve.