user: Question: Name the volume for co 2 for 168 g/km
Columns: ['Name', 'Volume', 'Engine', 'Fuel', 'Output', 'Torque', 'Engine ID code(s)', '0–100km/h,s', 'Top speed', 'CO 2', 'Years']
Types: ['text', 'text', 'text', 'text', 'text', 'text', 'text', 'text', 'text', 'text', 'text']
Sample row: ['1.4 16v', '1390 cc', '4cyl', 'Petrol', 'PS (kW; hp) @5000 rpm', 'N·m (lb·ft) @3300 rpm', 'AHW/AXP/BCA', '15.6', 'km/h (mph)', '163 g / km', '1999–2006']
SQL:

assistant: SELECT COUNT("Volume") FROM "Table" WHERE "CO 2" = '168 g/km';