Perhaps one of the most difficult trailers to watch released so far in 2009 features both Mariah Carey, Mo’nique and Lenny Kravits in Precious, due out in theatres in November. Clarice “Precious” Jones is a sixteen year old with big dreams–she wants to be on magazine covers and in videos on BET. Of course, she’s also got big difficulties–she’s sixteen, still in junior high and pregnant with her second child. But can she overcome her many struggles to make something of herself? Check out …