Identify the element, compound and mixture in the following picture

An element is a pure component, which can be distinguished into basic substances by physical or chemical means. In the given picture b is an element.  

Compound refers to a pure component formed of two or more elements, which are chemically bonded or combined. In the given picture c is a compound.  

Mixture refers to two or more components, which are mixed together but are not combined chemically. In the given picture, a is a mixture.  

the national environmental policy act (nepa) is a united states environmental law that promotes the enhancement of the environment and established the president's council on environmental quality (ceq). the law was enacted on january 1, 1970. to date, more than 100 nations around the world have enacted national environmental policies modeled after nepa.

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