Yes, they do exist. And the question is ... ?
It all depends what type of shape your talking about.
opposite angles in which type of quadrilateral?
5 angles, of course
It has two right angles
If you mean interior angles of 2800 degrees then no such polygon exist because one of its sides woud not meet up with another side.
The object you describe doesn't exist.
None. The angles do not exist and so there are no problems caused.
Yes, they do exist. And the question is ... ?
It all depends what type of shape your talking about.
opposite angles in which type of quadrilateral?
5 angles, of course
It has two right angles
Equal angles.
90 degrees angles or right angles.
It has 4 90 degree angles.
yes