New Delhi, Nov. 13 -- Delhi's air quality remained "severe" for a second straight day as a smog hung over the city, keeping pollutants trapped close to the surface due to dipping temperatures. The 24-hour rolling average air quality index (AQI) was 418 at 4pm, marginally lower than the 4pm reading of 428 on Tuesday. On Tuesday, Delhi recorded the worst AQI since December 19 last year, when it was 451, prompting enforcement of Stage-3 Grap measures. htc...