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In the graphic view, select one or more edges in a connected set of edges.
You can select the edges one by one, or you can use Chain 
on the ribbon to automatically select all connected edges based on the Merge Tolerance and Tangent Threshold settings.
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In the Merge Tolerance box on the ribbon, select or type a value. This value controls how close the endpoints of the edges must be.
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In the Tangent Threshold box, select or type a value. This value controls the chaining operation.