Question: what is the rank when the album is Sean Kingston?
SQL: SELECT "Rank" FROM "2-18382509-2" WHERE "Album" = 'Sean Kingston';

Question: how many times is the rank less than 6, certification 2x platinum and the peak position 2?
SQL: SELECT COUNT("Sales") FROM "2-18382509-2" WHERE "Rank" < 6.0 AND "Certification" = '2x platinum' AND "Peak position" = '2';

Question: what is the lowest rank when the peak position is 2, certification is Platinum and the album is My December?
SQL: SELECT MIN("Rank") FROM "2-18382509-2" WHERE "Peak position" = '2' AND "Certification" = 'Platinum' AND "Album" = 'My December';

Question: What is the sales when the artist is kelly clarkson?
SQL: SELECT COUNT("Sales") FROM "2-18382509-2" WHERE "Artist" = 'kelly clarkson';