J. S. Bach's Air "On the G-string" from his 3rd orchestral suite in D major, BWV 1068.
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Q: Where can I get free sheet music for this piece?
A: The score in the video can be downloaded from here:
http://www.musanim.com/pdf/air.pdf
And here's a piano arrangement of it
http://www.musanim.com/pdf/AirOnAShoeString.pdf
http://www.musanim.com/pdf/AirOnAShoeString_5thdown.pdf

Q: Who is performing?
A: I got this recording from Royalty Free Classical Music (dot org); they sell stock performances, and give stock answers to questions; the stock answer to "who is performing this" is "The RFCM Symphony Orchestra".

Q: What does this have to do with a g-string?
A: The short answer is that many people know it by the name "Air on the G-string," so I put it in the title to help people find it. You can read more about this here:
http://en.wikipedia.org/wiki/Air_on_the_g_string

Q: What is the real name of this piece?
A: It is the second movement of Bach's Orchestral Suite No. 3 in D major, titled "Aria" ("Air" is the English word for "aria").

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Q: Where can I download this recording?
A: There's a similar recording you can download free, from here:
http://tinyurl.com/airatmusopen

Q: What is the BWV number for this?
A: BWV 1068

Q: Can you please do a video of ___________?
A: Please read this:
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