In what year was the album “The Difference” released by Brave Girls?

In what year was the album “The Difference” released by Brave Girls?: The album “The Difference” was released in 2011 by Brave Girls, featuring 2 tracks.
What is the most successful song from the album “The Difference” by Brave Girls?: “Do You Know” is the biggest hit from the album “The Difference” by Brave Girls.

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