Review unique issues with annotating and dimensioning circles and arcs in the [Annotation Guide](https://github.com/LibreCAD/docs/blob/master/guides/annotate.rst): 1. Consistent center lines/marks 1. Label radius/diameter internal/external at angle Examples: 1. [Multiple circles through the same centre-point](https://forum.librecad.org/file/n5717860/diameters.png) - see https://heikell.fi/downloads/LibCAD_220rc1.pdf Exercise 5 p73 1. https://forum.librecad.org/file/n5718399/Bracket_dell.pdf - Side View: hole diameter, top arc diameter; End View: inner and outer radius