The Korean conglomerate responsible for Hyundai and Kia has agreed to pay $360 million to end the Environment Protection Agency’s investigation into the legitimacy of the car makers’ stated fuel-economy ratings. The settlement is the largest of its kind under the Clean Air Act and comes in response to allegations that the automakers fudged fuel-economy ratings for 1.2 million vehicles between 2011 and 2013. Of the total settlement, $210 million comes from forfeiting greenhouse-gas emission credits. The other $100 million will be paid as a civil penalty, and $50 million will be paid to ensure independent auditing.