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polyhedron

a solid figure bounded by plane polygons or faces

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face

cover the front or surface of

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edge

a sharp side formed by the intersection of two surfaces of an object

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vertex

the point of intersection of lines or the point opposite the base of a figure

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regular polyhedron

any one of five solids whose faces are congruent regular polygons and whose polyhedral angles are all congruent

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convex

curving or bulging outward

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cross section

(physics) the probability that a particular interaction (as capture or ionization) will take place between particles

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platonic solids

any one of five solids whose faces are congruent regular polygons and whose polyhedral angles are all congruent

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tetrahedron

any polyhedron having four plane faces

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octahedron

any polyhedron having eight plane faces

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dodecahedron

any polyhedron having twelve plane faces

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icosahedron

any polyhedron having twenty plane faces

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prism

optical device having a triangular shape and made of glass or quartz

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bases

compounds that reduce the concentration of hydrogen ions in a solution

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lateral faces

the faces that are not the base of a parallelogram

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right prism

each lateral edge is perpendicular to both bases

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oblique prism

a prism that is not a right prism

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surface area of a polyhedron

the sum of the areas of the faces of the polyhedron

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lateral area of a polyhedron

the sum of the areas of its lateral faces

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net

A two-dimensional pattern that can be folded to make a three-dimensional prism or pyramid

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cylinder

a solid bounded by a cylindrical surface and two parallel planes (the bases)

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right cylinder

a cylinder where the segment joining the centers of the bases is an altitude

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lateral area of a cylinder

2πrh

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surface area of a cylinder

2πrh+2πr²

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pyramid

a massive memorial with a square base and four triangular sides

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regular pyramid

a pyramid whose base is a regular polygon and whose lateral faces are congruent isosceles triangles

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circular cone

has a circular base and a vertex that is not in the same plane as the base

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lateral surface of a cone

pi r l

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right cone

A cone in which a perpendicular line drawn from the base to the tip (vertex) passes through the center of the base

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sphere

any spherically shaped artifact

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center of a sphere

The point inside a sphere that is the same distance from every point on the sphere.

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radius of a sphere

a segment that has one endpoint at the center and the other endpoint on the sphere

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chord of a sphere

a segment whose endpoints are on the sphere

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diameter of a sphere

chord that contains the center

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great circle

a circular line on the surface of a sphere formed by intersecting it with a plane passing through the center

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hemisphere

either half of the cerebrum

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similar solids

solids with the same shape and all their corresponding dimensions are proportional

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