汽车等机动车辆排放出的尾气在太阳紫外线的照射下可形成二次污染物。一天中污染物污染最严 发布时间:2022-01-28 17:47 │ 来源:www.tikuol.com 题型:单项选择题 问题: 汽车等机动车辆排放出的尾气在太阳紫外线的照射下可形成二次污染物。一天中污染物污染最严重的时间一般为A.凌晨B.上午C.中午D.傍晚E.夜晚
题型:单项选择题 选择合适的单词填空。Word Box: on book in front of chair gym1. What's it? It's a ___________. Where is it? It's ___________ the desk. 2. What's it ? It's a ___________.Where is it?It's ___________ the blackboard. 3. Where are they? They are in the ___________. 查看答案
题型:单项选择题 We should always bear in mind _________ many accidents ________ from drink-driving. [ ]A. which; raise B. that; arise C. which; arouse D. that; rise 查看答案
题型:单项选择题 (8分)一列货车的质量为5.0×105kg,在平直轨道以额定功率3000kw加速行驶,当速度由10m/s加速到所能达到的最大速度30m/s时,共用了2min,则这段时间内列车前进的距离是多少?g=10m/s2 查看答案