Answer: An instrument for measuring angles, typically in the form of a flat semicircle marked with degrees along the curved edge.
Step-by-step explanation:
A protractor is a semicircular tool used to measure and draw angles. It is usually made of transparent plastic, glass, steel, or wood. Protractors are commonly used in mechanics, engineering, and geometry.
Protractors are divided into 180 equal parts, each measuring 1°. They have an inner scale and an outer scale with markings from 0° to 180°. Protractors often have two sets of numbers going into opposite directions: 0° to 180° and 180° to 0°.