1.近年来,我国东北、华北和华东地区持续发生了沙尘暴天气,严重影响人们的工作、生活.造成这一现象的重要原因之一是( ). (A)火山爆发的结果(B)大气污染的结果(C)土壤污染的结果(D)植物遭受破坏的结果2.下列事实没有发生化学变化的是( ). (A)农村中,用牛马粪放入地窖中发热, 1. In recent years, dust storms continue to occur in the Northeast, North China, and East China regions, seriously affecting people’s work and life. One of the important causes of this phenomenon is (). (A) Results of volcanic eruptions (B) Atmosphere Contamination results (C) Results of soil contamination (D) Results of plant damage 2. The following facts did not occur chemical changes (). (A) In rural areas, cattle horse dung was placed in the cellar to generate heat,