user: Question: If length is ft (m) with numbers of 6600-6684 (84 buses) for 2003, what is the engine type?
Columns: ['Year', 'Make & Model', 'Length', 'Engine Type', 'Numbers']
Types: ['text', 'text', 'text', 'text', 'text']
Sample row: ['2000-2004', 'Orion VI', 'ft (m)', 'Diesel', '6000-6161 (160 buses)']
SQL:

assistant: SELECT "Engine Type" FROM "Table" WHERE "Length" = 'ft (m)' AND "Year" = '2003' AND "Numbers" = '6600-6684 (84 buses)';