Mercedes and Rachel team up for this duet of "Out Here on My Own." The single is taken from the show FAME.
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Mercedes and Santana teamed up for "The Boy is Mine" on the 5/11/10 episode of Glee. Listen to this audio version of the single and, simply put, enjoy.
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Take it away, Mercedes! In this clip from Glee, the character busts into a version of Jazmine Sullivan's "Bust Your Windows."
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Glee Quotes

Rachel: This is what I wanted!
Sam: No, what you wanted was a second chance to get it right and Carmen just gave it to you. If you throw all that away you're going to be making the same mistake all over again

Finn: I seem to recall a rumor about a certain cheerleading coach at this school who once took horse estrogen and posed for Penthouse back in the day. So maybe I can just track that down and make a few copies and sell those to raise money for Regionals.
Sue: That's nothing but a rumor. But if that rumor were true, my Penthouse centerfold so groundbreaking that it completely redefined the term 'hirsute,' and gave birth unto these United States a pose so limber they named it the Regal American Not-So-Bald Spread Eagle, I promise you, my friend, you would never find it.