AC and BD are parallel secants. [br][br]A. Check the box to highlight arcs and show arc measures. Drag the points to adjust the lines. [br][br]1. How do the arcs change? When are they largest? Smallest?[br]2. How do the arc measure relate to each other?[br][br]B. Check the box so that the arcs and arc measures are not shown. Click to show the transversal and alternate interior angles. Drag the points to adjust the lines. [br]1. What kind of angle pairs are angles CAD and BDA?[br]2. Which arcs do CAD and BDA intercept?[br]3. How do the measures of angles CAD and BDA relate? [br]4. Can you explain why arcs AB and DC will always be congruent by describing the relationship between CAD and BDA?