Since Enactment of the Highway Beautification Act of 1965, the Number

question 27

True/False

Since enactment of the Highway Beautification Act of 1965, the number of outdoor signs has risen from 400,000 to 1.2 million and continues to climb.

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Definitions:

Silicate Minerals

A group of minerals that contain silicon and oxygen, usually with other metals, forming the largest and most important class of minerals on Earth.

Double Chains

Structures consisting of two parallel chains of atoms or molecules bonded together, often found in silicate minerals.

Silicon Tetrahedron

A structural unit in silicate minerals, consisting of a central silicon atom covalently bonded to four oxygen atoms at the corners of a tetrahedron.

Silicate Minerals

Minerals that contain silicon and oxygen, and possibly other elements, constituting the largest family of minerals.