SELECT us_national_average_electric_mix FROM table_16105186_2 WHERE midwest__des_moines_ = "280 g/mi (174 g/km)"
Berapa peringkat campuran listrik rata -rata nasional AS untuk kendaraan yang diberi peringkat 280 g/mi (174 g/km) di Midwest?
CREATE TABLE table_16105186_2 (us_national_average_electric_mix VARCHAR, midwest__des_moines_ VARCHAR)