Table: giro_2011
Columns: stage
winner
general_classification
points_classification
mountains_classification
young_rider_classification

Question: When Alberto Contador Kanstantsin Sivtsov was the general classification and Alessandro Petacchi was the points classification at the same time while Mark Cavendish is the winner, who was the mountain classification?
SQL: SELECT "mountains_classification" FROM giro_2011 WHERE "general_classification" = 'Alberto Contador Kanstantsin Sivtsov' AND "points_classification" = 'Alessandro Petacchi' AND "winner" = 'Mark Cavendish'

Question: Who was the young rider classification when Alessandro Petacchi won?
SQL: SELECT "young_rider_classification" FROM giro_2011 WHERE "winner" = 'Alessandro Petacchi'

Question: Who was the young rider classification when Diego Ulissi won? 
SQL: SELECT COUNT("young_rider_classification") FROM giro_2011 WHERE "winner" = 'Diego Ulissi'

Question: What is the name of the young rider classification when Paolo Tiralongo won?
SQL: SELECT "young_rider_classification" FROM giro_2011 WHERE "winner" = 'Paolo Tiralongo'