A parallelogram has 4 corners or vertices
Yes. The corners must be right angles for it to be inscribed on the circle.
4 corners(angles).
4
It has 4 corners and 4 sides because it is a quadrilateral polygon
Four. Examples are parallelogram, rectangle, square etc
A sphere has no corners, it is a 3-D circle.
None
A semi-circle is a 180 degree half circle. A semi-circle does not have any corners. A circle does not have corners either. There are points of beginning and end in a semi-circle. In a circle the point of beginning is the same as the ending point.
A circle normally has no corners
The number of square corners in a circle is infinite because it has no definite angle.
A circle has only one side and it is called its circumference.