20070201
  k  Freehand Drawing
  Description
  You can use the pen option for freehand drawing in a graph. 
  Set Up
  1. Draw the graph.
  
  Execution
  2. Press !4 (SKTCH)6 (g )6 (g )1 (PEN), and a pointer appears in the center of 
the screen.
  3. Use the cursor keys to move the pointer to the point from which you want to start 
drawing, and then press w .
  4. Use the cursor keys to move the pointer. A line is drawn wherever you move the pointer. 
To stop the line, press w .
    Repeat step 3 and 4 to draw other lines.
  
5-10-5
Changing the Appearance of a Graph