Answer:
The answer is m∠ M'N'O' = m∠MNO
Explanation:
If the Angle MNO is rotated 90 degrees counterclockwise about the origin. The new angle formed by ' will be the same as the rotation doesn't alter neither the shape or size of the figure. Therefore, we can conclude that MNO and M'N'O' are congruent (Same lenght and angle).