Centroid, Incenter, Circumcenter, and Orthocenter – Lecture 16 (Geometry)

Intuitively, a set is best described as:

1. A.An ordered list where duplicates are counted separately.
2. B.An unordered, unique collection of elements.
3. C.A sequence of points satisfying an equation.
4. D.A pair of objects related by an operation.