Angle Formed by 2 Chords (V1): What Do You See?

Angles, Circle
Recall that a CHORD is a segment whose endpoints lie on a circle. In the applet below, note that the purple angle is formed when the two chords intersect. This angle formed by two chords intercepts two arcs. One intercepted arc is red. The other intercepted arc is blue. Drag the green slider and carefully watch what happens. Feel free to move any of the points of the circle around to change the location of the purple angle formed. As you move them, make sure that the 2 chords intersect each other! Answer the questions that follow the applet.
Please respond to the following prompt: From what you've seen, describe how you believe you can find measure of an angle formed by two chords of a circle. (Be sure to use the term "intercepted arc" or "intercepted arcs" at least once in your description.