Same-Side Interior Angles

Lines AB and FC are parallel. Line BC is a transversal.
1. Use points A, B, and C to move the lines. Observe the angle values. 2. <ABC and <FCB are same-side interior anlges. Name another pair of same-side interior angles. 3. What is always true about same-side interior angles formed when parallel lines are intersected by a transversal? 4. Prove your conjecture from question #3.