How can tartar and plaque be removed from teeth without grinding? is there any paste, etc. for it?
The girders of a suspension bridge form an arc. The definition of an arc is a curve or bowed shape, like a part of a circle. An example of an arc is a rainbow. To arc is defined as to make a curved shape or move in a curved path.
Ray: Definition and Examples A ray is a line with an endpoint that extends infinitely in one direction. One of the most obvious examples is a sun's ray of light in space.