Which of the following letters have rotational symmetry?
R, B, F, H, O, P, S, W, X, Z, N

Answer

To determine which letters have rotational symmetry, we will analyze each letter based on its ability to look the same after being rotated at certain angles.

### Step-by-Step Solution:

1. **Analyze Letter R**:
- When you rotate R by 360 degrees, it looks the same, but this is not considered rotational symmetry.
- **Conclusion**: R does not have rotational symmetry.

2. **Analyze Letter B**:
- Similar to R, B also looks the same only after a full 360-degree rotation.
- **Conclusion**: B does not have rotational symmetry.

3. **Analyze Letter F**:
- F also requires a full 360-degree rotation to look the same.
- **Conclusion**: F does not have rotational symmetry.

4. **Analyze Letter H**:
- When you rotate H by 180 degrees, it looks the same.
- **Conclusion**: H has rotational symmetry (180 degrees).

5. **Analyze Letter O**:
- O can be rotated by any angle (including 180 degrees) and still looks the same.
- **Conclusion**: O has rotational symmetry (infinite symmetry).

6. **Analyze Letter P**:
- P requires a full 360-degree rotation to look the same.
- **Conclusion**: P does not have rotational symmetry.

7. **Analyze Letter S**:
- When rotated by 180 degrees, S looks the same.
- **Conclusion**: S has rotational symmetry (180 degrees).

8. **Analyze Letter W**:
- W looks the same only after a full 360-degree rotation.
- **Conclusion**: W does not have rotational symmetry.

9. **Analyze Letter X**:
- X has rotational symmetry at both 90 degrees and 180 degrees, depending on how it's written.
- **Conclusion**: X has rotational symmetry (90 degrees and 180 degrees).

10. **Analyze Letter Z**:
- When rotated by 180 degrees, Z looks the same.
- **Conclusion**: Z has rotational symmetry (180 degrees).

11. **Analyze Letter N**:
- When rotated by 180 degrees, N looks the same.
- **Conclusion**: N has rotational symmetry (180 degrees).

### Final List of Letters with Rotational Symmetry:
- H (180 degrees)
- O (infinite symmetry)
- S (180 degrees)
- X (90 degrees and 180 degrees)
- Z (180 degrees)
- N (180 degrees)