How is the angle at the centre related to arc length, area of sector and radius?
This version allows either arc length or area of sector to be compared against angle and radius
Comments for further refinement :
1. Reposition visuals and reduce visible text (use buttion to activate instructions, formula etc)
2. Highlight table columns arc length or area of sector when either this mode is in focus.
3. Turn selection of point B, C off if sliders are used to control radius and angle respectively. Be consistent, either both slider or draggable points
4. If sliders are used, make them horizontal
5. The two way button is confusing, just use the text "button" activation.
