What tool is commonly used to measure and draw angles?

A protractor is specifically designed for measuring and drawing angles, making it the correct choice for this question. It typically has a semi-circular or circular shape with degree markings from 0 to 180 degrees (or 0 to 360 degrees in a full protractor), allowing users to accurately identify the size of an angle by aligning one side of the angle with the zero line and reading the measurement where the other side intersects the degree markings.

While a ruler is useful for measuring lengths and drawing straight lines, it does not provide the capability to measure angles. A compass is primarily used for drawing circles or arcs and may assist in geometric constructions but does not measure angles directly. A set square helps in creating right angles or specific angle measurements in conjunction with a ruler, but it is not used independently to measure angles like a protractor does.