Mathematics for IGCSE & O level - Geometrical Constructions (Section 3 - No. 23)
How does a semi-circular protractor differ from a full-circle protractor?
It can measure angles up to 180°
It is in the shape of a semi-circle.
It can measure angles up to 360°.
All of the above.
解释
A semi-circular protractor can measure up to 180 degrees, and is semi-circular. This leaves the remaining options to be the definition of the full-circle protractor.