What shape is a road-roller ?

Answer

To determine the shape of a road roller, we can follow these steps:

### Step-by-Step Solution:

1. **Observation of a Road Roller**:
- A road roller is a machine used in construction to compact surfaces like roads.

2. **Identifying the Main Part**:
- The primary component of a road roller is its large cylindrical drum that rolls over the surface to flatten it.

3. **Understanding the Shape**:
- The shape of the drum can be described as a cylinder. A cylinder has two circular bases and a curved surface connecting them.

4. **Describing the Dimensions**:
- The cylinder has a certain height (h) and a radius (r). The radius is the distance from the center of the circular base to its edge.

5. **Conclusion**:
- Therefore, we can conclude that a road roller has a cylindrical shape.

### Final Answer:
A road roller has a cylindrical shape.

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