Google is a web search engine where a software system that is designed to search for information on the World Wide Web, while subject directory, <span>unrelated to search engines in that, it is created and maintained by human and editors, like Wikipedia.</span>
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Without knowing the context some times the point the author is trying to get across can be viewed in different ways.
It could mean either depending on the context
1 is B
2 is a
hope this helps
Staging area most likely is, supply air lock <em>maybe</em> is, I'm not sure, and hot zone is.