CREATE TABLE table_name_30 (iata VARCHAR2, state_territory VARCHAR2, icao VARCHAR2)

What IATA has queensland as the state/territory and an ICAO of ybrk?
SELECT iata FROM table_name_30 WHERE state_territory = "queensland" AND icao = "ybrk"
SELECT "iata" FROM "table_name_30" WHERE "icao" = "ybrk" AND "queensland" = "state_territory"