1. The problem is to identify and understand obtuse angles as shown in the graphs labeled 11), 12), and 14). 2. An obtuse angle is defined as an angle greater than 90° and less than 180°. 3. The formula to check if an angle $\theta$ is obtuse is: $$90^\circ < \theta < 180^\circ$$ 4. For each angle in 11), 12), and 14), since they are labeled "obtuse," their measures satisfy this inequality. 5. This means each angle is larger than a right angle (90°) but smaller than a straight angle (180°). 6. Understanding this helps in classifying angles and solving geometry problems involving angle measures. Final answer: The angles in 11), 12), and 14) are obtuse because their measures are between 90° and 180°.