which best describes a mixture? it has a single composition, and it has a set of characteristics that does not change. it can have different compositions, but it has a set of characteristics that does not change. it has a single composition, but it has a set of characteristics that does change. it can have different compositions, and it has a set of characteristics that does change.

The correct statement is that it can exhibit different compositions, however, it has a set of characteristics that do not change.  

In science, mainly in chemistry, a mixture is formed when one combines two or more components and each of the components exhibits its own chemical characteristic. In order to consider as a mixture, the substances cannot dissociate or form chemical bonds with each other. To be a mixture, the substances must follow three usual characteristics, that is, they keep their own chemical properties, they can be easily distinguished, and the ratio of the components is variable.  

2b2t

explanation:

2b2t

metals are good conductor of electricity. it has free electrons on their surface. according to electron pool theory, each atom present in a metal crystal losses all of its valence electron and as a result a pool of free is form. these pool of electrons are free to move and   conduct electricity easily   while making metal as good conductor.

the correct answer is a. the ability of electrons to flow throughout the metal.

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