Being able to identify an angle can help us in this lesson. Let's try this problem to review.
Which of the following is a right angle?
Look for the angle with a small square in the corner.
Option A has a small square at the corner, so the answer is option A.
A right angle is exactly 90\degree.
This video explains about acute, right, obtuse, straight, and reflex angles, as well as revolutions.
Select the obtuse angle:
Use this image to help you:
Rotate each angle so that one arm lies over the start.
The answer is Option C.
A full revolution is made up of 360 degrees, a single degree is written 1\degree.