Comprehensive geometry worksheet helping students practice identifying different types of angles through visual diagrams and degree measurements.

To solve the problem, we need to classify each angle as acute, obtuse, right, or straight. Here's a step-by-step explanation of how to do this:

Definitions:

1. Acute Angle: An angle that measures less than 90°.
2. Right Angle: An angle that measures exactly 90°.
3. Obtuse Angle: An angle that measures more than 90° but less than 180°.
4. Straight Angle: An angle that measures exactly 180°.

Solution:

#### Part 1: Visual Angles (1-10)
We will analyze each visual angle and determine its classification based on its appearance.

1. Angle 1: This angle is less than 90°.
Classification: Acute

2. Angle 2: This angle is exactly 90°.
Classification: Right

3. Angle 3: This angle is more than 90° but less than 180°.
Classification: Obtuse

4. Angle 4: This angle is less than 90°.
Classification: Acute

5. Angle 5: This angle is exactly 180°.
Classification: Straight

6. Angle 6: This angle is more than 90° but less than 180°.
Classification: Obtuse

7. Angle 7: This angle is more than 90° but less than 180°.
Classification: Obtuse

8. Angle 8: This angle is exactly 90°.
Classification: Right

9. Angle 9: This angle is less than 90°.
Classification: Acute

10. Angle 10: This angle is more than 90° but less than 180°.
Classification: Obtuse

#### Part 2: Numerical Angles (11-20)
We will classify each angle based on its given measure.

11. 84°: This angle is less than 90°.
Classification: Acute

12. 89°: This angle is less than 90°.
Classification: Acute

13. 25°: This angle is less than 90°.
Classification: Acute

14. 50°: This angle is less than 90°.
Classification: Acute

15. 180°: This angle is exactly 180°.
Classification: Straight

16. 166°: This angle is more than 90° but less than 180°.
Classification: Obtuse

17. 90°: This angle is exactly 90°.
Classification: Right

18. 125°: This angle is more than 90° but less than 180°.
Classification: Obtuse

19. 149°: This angle is more than 90° but less than 180°.
Classification: Obtuse

20. 106°: This angle is more than 90° but less than 180°.
Classification: Obtuse

Final Answer:

\[
\boxed{
\begin{array}{ll}
1. \text{Acute} & 6. \text{Obtuse} \\
2. \text{Right} & 7. \text{Obtuse} \\
3. \text{Obtuse} & 8. \text{Right} \\
4. \text{Acute} & 9. \text{Acute} \\
5. \text{Straight} & 10. \text{Obtuse} \\
11. \text{Acute} & 16. \text{Obtuse} \\
12. \text{Acute} & 17. \text{Right} \\
13. \text{Acute} & 18. \text{Obtuse} \\
14. \text{Acute} & 19. \text{Obtuse} \\
15. \text{Straight} & 20. \text{Obtuse} \\
\end{array}
}
\]