Viruses are not considered "alive" because they lack many of the properties that scientists associate with living organisms. Primarily, they lack the ability to reproduce without the aid of a host cell, and don't use the typical cell- division approach to replication.
This could be two answers Water or Oxygen. I would go with water because it contains oxygen therefore making it a possible answer. Hope I helped. :)
Answer that does not describe the structure of an atom: The electron clod is a small and compacted space around the nucleus.
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because you never know when ur gonna need it