Below is an context that describes a sql query, paired with an question that provides further information. Write an answer that appropriately completes the request.  # noqa: E501
### Context:
CREATE TABLE table_17941111_2 (volume VARCHAR, co_2 VARCHAR)
### Question:
Name the volume for co 2 for 168 g/km
### Answer:
SELECT volume FROM table_17941111_2 WHERE co_2 = "168 g/km"