To Create a Chain of Arcs
1. On the Home tab click the arrow next to Line.
2. Click Line/Arc Chain.
3. Select a start point for the arc. A line segment rubberbands between the start point and the pointer.
4. Press the S key. The rubberbanding line changes to a rubberbanding arc and looks as if it is tracing a part of a circle.
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If you press the S key again, you return to Line Creation mode.
5. Click another location to complete the arc. The Line/Arc Chain tool toggles back to the Line Creation mode.
6. Continue creating lines or arcs.
7. Middle-click or press ESC to exit the tool.