How can I draw a tangent line off an arc within a polyline

You may have noticed that when you go to the ARC mode within the PLINE command, the first and consecutive arcs are tangent to the previous segment. To create a tangent line off the last segment, first press L for Line mode, then press a second L for Length.  Pick or enter a distance and the segment drawn will be tangent off the last arc. It’s the 2nd L that does the trick.