circles angles of intersecting chords, secants and tangents

Demonstration of relationships between two secants, chords and the angles of intersection and the central angles. Move points:D,E,F along the circle to change the angles. Can Illustrate the relationships of inscribed angles, tangents, secants intersecting inside and outside circle.
When Point C is inside the circle how is m<C related to the major and minor arc measures? What kind of angle is show when the minor arc is zero degrees? When you move point C so It gets closer to the circle, What is happening to the central angles (or arcs)? When Point C is on the circle, what is happening to the central angles (or arcs)? When point C is moved from the inside the circle to the outside what happened to the minor arc? Relate this to the two formulas { <C= 1/2( arc(DB) +arc(EF) ) & <c= 1/2( arc(DB) - arc(EF) ) }