Conversation so far:
What was the line up changes South Korean group Kara faced?
South Korean group Kara Members Nicole Jung and Kang Ji-young officially departed from the group in 2014, while Kim Sung-hee left in 2008.
Why did Kang Ji-young leave the group Kara?
Kang Ji-young left South Korean group Kara because her contract was expiring and to puruse her other dreams.
Who was Kang Ji-young eplaced with?
South Korean group Kara member Kang Ji-young was replaced with Youngji.
What were the names of the two new members of Kara?
The two new members of South Korean group Kara are Younji and Hara.
What is Rock U by Kara?
Rock U is the first mini-album by South Korean girl group Kara.

Question: How did this album do on the charts?
Self-contained rewrite: How did the album Rock U by Kara do on the charts?