Which type of hull is designed to operate at slower speeds and has a round bottom?

A displacement hull is designed to operate efficiently at slower speeds and features a round bottom. This design allows the hull to move through the water by displacing a volume of water equal to its own weight. As a result, displacement hulls are typically found on larger vessels and are characterized by a smooth, stable motion. They maintain their speed by pushing water aside rather than skimming over the surface, making them particularly suitable for cruising and long-distance travel.

The other types of hulls listed, such as planning hulls, are designed for higher speeds and have a flatter underside that allows them to glide over the water's surface. Catamaran hulls consist of two parallel hulls and provide greater stability and speed, while flat-bottomed hulls are often more suitable for shallow waters but can be less stable in rough conditions. Thus, the design and functionality of a displacement hull make it ideal for slower, more stable voyages on the water.