Response:
A) There is an issue here because the dimensions are not specified.
For instance, the set {1, 3}
Represents all locations that maintain a consistent distance (1 unit) from the point at x = 2.
If we redefine it as:
"A planar shape whose points maintain a fixed distance from a certain point, called the center".
This implies that we are referring to a "planar figure," necessitating a plane to create a figure, which implies the necessity of two dimensions, avoiding any confusion in this definition.
B) Undefined terms refer to concepts lacking formal definitions: those include point, line, plane, and set.
A circle requires a plane (as it exists within a plane), and a circle is essentially the collection of all points equidistant from a center point within that plane.
This necessitates the use of a minimum of three undefined terms to define a circle.
