Does Brittany Murphy really sing in "The Little Black Book"?

Question

While she is laying on the bathroom floor singing :Nobody Does It Better", is that actually her, or Carly Simon, or somebody else?
Please list the source in which you got it from.

Answer 1

I would assume so because she used to be in a band Blessed SOul in the 90's so she can sing.

Answer 2

Yes

Answer 3

yeah..