Whoopi Time: Whoopi Goldberg, who performed at the San Diego Repertory Theatre 15 years before she won the 1991 Academy Award for best supporting actress for "Ghost," will present two benefit performances of her new one-woman show for the financially strapped theater on May 15. The show, "Whoopi Goldberg . . . I'm Back," will premiere new monologues and sketches written and performed by Goldberg in what will mark her first live stage appearance since her acclaimed 1988 Broadway run.