It is called a semi protractor and the fully-circular one is called an angle measurer
The instrument used to measure the angle between two lines is called a protractor. A protractor typically consists of a semicircular or circular tool with markings for degrees. To measure the angle, the protractor is placed along one line with the center point at the intersection of the two lines, and the angle is read where the second line crosses the protractor.
A protractor is used to measure an angle.
A protractor can be used to measure an angle.
The instrument used to measure a angle is called a protractor!
The instrument you are looking for is a compass
A protractor.
the vertex of the angle
A protractor is used to measure an angle
Sure - just bisect it twice.
A sextant.
A protractor is an instrument that is used when you need to measure an angle.
Some of the devices used to measure angle are Transit, Protractor and Compass.