A parallelogram has 4 vertices
A parallelogram has 4 corners or vertices
Four.
4.
A parallelogram has four vertices- it's a quadrilateral.
4 sides and 4 vertices
4
Not sure about a parallelgram, but a parallelogram has 4.
It is a flat faced 4 sided quadrilateral that has 4 vertices.
Yes and it has 4 of them.
12 vectors, unless it is a parallelogram (13 if you include the null vector). If the quadrilateral is a parallelogram there will be two fewer.
No because the diagonals of a parallelogram are of different lengths