What geometry theorem is being dynamically demonstrated in the applet below? [br](Feel free to move the points anywhere you'd like!)
[color=#000000][b]Theorem:[/b][/color][br][br]A [color=#1e84cc][b]diameter[/b][/color] that is drawn [color=#ff00ff][b]perpendicular[/b][/color] to a [color=#38761d][b]chord[/b][/color] bisects that [color=#38761d][b]chord[/b][/color] and the [color=#38761d][b]arc[/b][/color] that [b][color=#38761d]chord[/color][/b] determines.