An angle that measures exactly 90° is a ___________.

The angle is called a right angle if the measure of the angle between two rays is exactly equal to 90 degrees

Angles less than 90°, such as 87°, 56°, 77°, 42°, and so on, are called acute angles, while angles greater than 90°, such as 91°, 98°, 102°, 150°, 167°, and so on, are called obtuse angles.