the resulting three-dimensional figure is called a prism. the triangular region.....is called the base of the prism and the triangular region.....is called the upper base of the prism.
since the bases are congruent triangles ,this figure is called a triangular prism.Line segments...........are called lateral edges of the prism .A perpendicular line segment between the two planes,indicated by ..in the figure,is called an altitude of the prism.