Write 4-6 sentences describing how many acute and obtuse angles are created when 2, 3, or 4 parallel lines are crossed by a single transversal that is not perpendicular to them. Create pictures to help. Identify how many unique acute angle measures there are and how many unique obtuse angle measures there are, explaining your reasoning. Propose a generalization for when there are no parallel lines, and confirm the generalization matches what was found for the cases of 2, 3, or 4 parallel lines. Prove the generalization, explaining all of your reasoning.