Polyhedron what are they

In geometry, a polyhedron is a three-dimensional shape with flat polygonal faces, straight edges and sharp corners or vertices. The word polyhedron comes from the Classical Greek πολύεδρον, as poly- + -hedron. A convex polyhedron is the convex hull of finitely many points, not all on the same plane.

A polyhedron is a 3-D shape with flat polygonal faces (think complete flat shapes with no curvatures), straight edges, and sharp vertices (corners).

a. the residual plot for model 1 has a random pattern and is a good fit for the data.

no not all of them.

step-by-step explanation:

some of them have a square base.