[By Arc to Point]command extends(extrapolates) an existing curve as an arc shape curve. The extending curve is so generated that the two tangents and the two curvatures are continuous at the connectiong points.
For the prompt
"Specify around an end point of a curve"
, mouse-click around an end
point of a target curve to extend.
For the prompt
Specify destination point
, specify an end point of the extending part of
curve.