Answer:
2 times.
Explanation:
Since, in a parallelogram the diagonals of bisect each other,
And, this point of intersection is called mid point of the diagonals of the parallelogram,
Also, the distance of any vertex of a figure from the point rotation is same as the distance of vertex of the transformed figure from the point of the rotation,
Therefore, if a irregular parallelogram rotates 180° about the midpoint of its diagonal, then the image of the parallelogram coincide with its preimage after the rotation.
Hence, If a irregular parallelogram rotates 360° about the midpoint of its diagonal, then the image of the parallelogram coincide 2 times with its preimage during the rotation.
First option is correct.