Question: What stage number had the general classification Rory Sutherland?
SQL: SELECT COUNT("Stage") FROM "1-23157997-13" WHERE "General classification" = 'Rory Sutherland';

Question: Who was the Youth Classification in the race with Kenneth Hanson as Mountains Classification and Lucas Sebastian Haedo as winner?
SQL: SELECT "Youth classification" FROM "1-23157997-13" WHERE "Mountains classification" = 'Kenneth Hanson' AND "Winner" = 'Lucas Sebastian Haedo';

Question: Who won the race with Tom Zirbel as Mountains Classification and Thomas Soladay as Points Classification?
SQL: SELECT "Winner" FROM "1-23157997-13" WHERE "Mountains classification" = 'Tom Zirbel' AND "Points classification" = 'Thomas Soladay';

Question: Who was Mountains Classification in the race with Nick Frey as Youth Classification and Tom Zirbel as Points Classification?
SQL: SELECT "Mountains classification" FROM "1-23157997-13" WHERE "Youth classification" = 'Nick Frey' AND "Points classification" = 'Tom Zirbel';

Question: How many Mountains Classifications were in the race with Mike Northey as Youth Classification?
SQL: SELECT COUNT("Mountains classification") FROM "1-23157997-13" WHERE "Youth classification" = 'Mike Northey';