Menu: Draw / Circle / Tangent to 3 Arcs 
Creates a circle tangent to three arcs or circles. You can specify whether the existing arcs will be inside or outside the new circle.
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If the object is clicked slightly outside, an outward-pointing arrow appears. 
- Select the second tangent object.
If the object is clicked slightly inside, an inward-pointing arrow appears. 
- Select the third object. The tangent circle is created.
