1* Path->Create Circle... -> Number of Sections:
2* Path->Create Arc... -> Arc params:
3* PathManipulator->Context Menu->
4	* Transform (creates TransformBox)
5	* Cut
6	* Copy
7	* Paste (replacing first selected points, or appended at end)
8	* Soften (available at hard edge(s),
9			  inserts points for round corner,
10			  asks for radius)
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