A business may not provide you with a service or benefit if you donât provide your number. Sometimes you will have to share your number. Your employer and financial institutions need your SSN for wage and tax reporting purposes.
An arc is a portion of the circumference of a circle. In the figure above, the arc is the blue part of the circle. Strictly speaking, an arc could be a portion of some other curved shape, such as an ellipse, but it almost always refers to a circle. To avoid all possible mistake, it is sometimes called a circular arc. A straight line is drawn between the end points of the arc would be a chord of the circle. If the arc length is exactly half the circle, this called a semicircular arc. See Semicircle definition.
spiral (plural spirals) ( 1 geometry) A curve that is the locus of a point that rotates about a fixed point while continuously increasing its distance from that point. ( 2 informal) A helix. 3  A self-sustaining process with a lot of momentum involved, so it is difficult to accelerate or stop it at once.