Why should photovoltaic panels be connected to a combiner box

What part of speech is "why" in the following example?

In the sentence "Why is this here?", is "why" an adverb? What part of speech is "why?" I think it modifies the verb "is", so I think it is an adverb.
"Why it is" vs "Why is it"

9 1) Please tell me why is it like that. [grammatically incorrect unless the punctuation is changed. Please tell me: Why is it like that? The question: "Why is [etc.]" is a question form
"Why?" vs. "Why is it that ?"

I don''t know why, but it seems to me that Bob would sound a bit strange if he said, "Why is it that you have to get going?" in that situation.
etymology

I know it originates from "head shrinking", but it doesn''t help me a lot to understand the etymology. Why are psychiatrists called that? Is it like "my head is swollen [from anguish, misery, stress...
Difference between how and why

The questions How? and Why? only have similar answers where the reason for something is the cause. This is the case for a question like "Why is the boy so big?" — he has
Why are the people of the United States called "Americans" when

So to answer the question as to why we think of the United States when we say "Amerikaner", "Américains", "americani" - I think it''s simply an expression of the importance
Where does the use of "why" as an interjection come from?

"why" can be compared to an old Latin form qui, an ablative form, meaning how. Today "why" is used as a question word to ask the reason or purpose of something. This use
Can "why" be a conjunction?

Why is a just a rather odd wh -word. Its distribution is very limited -- it can only have the word reason as its antecedent, and since it''s never the subject it''s always deletable.
Why is it called hypochondria instead of hyperchondria?

Why is it called hypochondria instead of hyperchondria? [closed] Ask Question Asked 5 years, 6 months ago Modified 5 years, 6 months ago
etymology

The history told me nothing why an involuntary, extremely painful spasm, is named after a horse called Charley. Charley in the UK is often spelled Charlie, a diminutive of