Which tool would likely be used for manual one-handed tasks?

The hand hatchet is particularly suited for manual one-handed tasks because it is designed for precision and control. Its lightweight and ergonomic features allow for efficient use with one hand, making it ideal for activities such as trimming, cutting, or shaping materials. The narrow blade and sharp edge facilitate tasks that require accuracy without needing the additional force or two-handed grip that other tools would necessitate.

In contrast, the other tools mentioned typically require two hands or are designed for different types of tasks. A sledge hammer is a heavy tool that is meant for delivering powerful strikes, which demands both hands for safe and effective usage. Cotter pins are small fasteners and are not used for manual tasks in the same sense; they serve specific functions in securing components together but do not fit within the realm of one-handed manual tools. Lastly, the ball peen hammer, while more manageable than a sledge, is still not the optimal choice for one-handed work as it is better used for striking and shaping tasks that benefit from stability and control with a two-handed approach.