No, but a parallelogram is a polygon.
Yes
2
paralellagram
Two (or none, if it is a rectangle).
It depends on what measure is missing.
Not normally unless it is in the shape of a rectangle.
Yes, all sides and angles are equal and parallel.
Paralellagram, Square or Rectangle
base times height is area
Paralellagram
They are all misspelled.
It belongs in the class of quadrilaterals that all have 4 sides