Answer:
2. are connected sequences of lines and arcs
Step-by-step explanation:
A polyline is an object that is compound in nature as it includes one or more linear or curved segments. It is made up of connected sequence of lines and arcs that are created as a single object rather than individual objects.
Polylines are useful in the following;
i. Easy creation of rectangles and polygons as a single entity.
ii. In AUTOCAD, they allow for easy extrusion for 3D solids.