Three.
A recangle has 4 line segments. (Each side is a line segment).
No. A polygon must have at least three line segments.
Straight
4
4
A quadrilateral.
At least three.
Depending on how you choose to define a line segment, you may conclude that the letter E has 4 or 5 line segments.
A quadrilateral has 4 line segments
4
They can not be line segments on the same line, but they can both be line segments.