Question

unit 1 lesson 13 cumulative practice problems

1. select all the polyhedra.

a
b
c
d
e
a. a
b. b
c. c
d. d
e. e

Explanation:

Step1: Recall polyhedron definition

A polyhedron is a three - dimensional solid with flat polygonal faces, straight edges and sharp vertices.

Step2: Analyze Option A

It is a pyramid with triangular faces and a polygonal base, so it is a polyhedron.

Step3: Analyze Option B

It has flat polygonal faces, straight edges and vertices, so it is a polyhedron.

Step4: Analyze Option C

A cone has a curved surface, so it is not a polyhedron.

Step5: Analyze Option D

It is a prism with flat polygonal faces, straight edges and vertices, so it is a polyhedron.

Step6: Analyze Option E

A sphere has a curved surface, so it is not a polyhedron.

Answer:

A. A
B. B
D. D