The third has a triangular cross-section. (Sometimes the ‘cross-section’ is called the 'base'.) The distance between the two ends of the prism is always called the height of the prism even if ...

When the cross-section is a triangle, the prism is called a triangular prism. When the cross-section is a hexagon, the prism is called a hexagonal prism. The surface area is made up of the end ...