Measures the angle between three points, or between two lines.
- Select three points that define the angle you want to measure.
Local menu option: By Entity: Measures the angle between two lines. The lines must intersect (this tool does not infer where extensions of lines will meet). 
- Select the first line. The point you select on the line defines the angle that will be measured.
- Select the second line, and the angle is displayed.
