From August 10 to August 20, 2018, how many cancelled flights of air carrier named Spirit Air Lines: NK are there?
From August 10 to August 20, 2018 refers to FL_DATE BETWEEN '2018/8/10' AND '2018/8/20'; cancelled flights refers to CANCELLED = 1; Trans Southern Airways: 'Spirit Air Lines: NK' refers to Description = 'Spirit Air Lines: NK';
SELECT COUNT(*) FROM `Air Carriers` AS T1 INNER JOIN Airlines AS T2 ON T1.Code = T2.OP_CARRIER_AIRLINE_ID WHERE T1.Description = 'Spirit Air Lines: NK' AND T2.CANCELLED = 0 AND T2.FL_DATE BETWEEN '2018/8/10' AND '2018/8/20'