Anewstudylinksheavyairpollutionfromcoalburningtoshorter...
问题详情：AnewstudylinksheavyairpollutionfromcoalburningtoshorterlivesinnorthernChina.Researchersestimatethatthehalf-billionpeoplealivethereinthe1990swillliveanaverageof5yearslessthantheirsoutherncounte...