What are the celebrity roles of Sharpey in th video of the song 'I want it all'

[genineG]

in High School Musical? Its really bugging me can anybody help??
i thought the frst was gwen stefani or christina agulaira couldn't tell because im always getting mixed up between the 2 thanx stella
i also think one of them could be hannah montana/ miley cyrus

 

[Stella]

I don't know all of them, but I'm extremely sure that one of them was Gwen Stefani.. because of her hair and lipstick.

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