【简答题】大气是多种气体的混合物,其组成主要包括()三种组分。
【单选题】氮氧化合物是氮的氧化物的总称。通常所指NO和NO2两种成分的混合物,是大气中常见的重要污染物,其主要污染源为( )。
B.
燃料燃烧时,空气中的氧和氮在高温下生成的产物
【判断题】大气是 由多种气体混合组成的气体及悬浮在其中的固态和液态杂质所组成 的混合物,主要成分是 氮气、氧气、氩气 ,此外还有含量不定的 液态 、 固体杂质 微粒。
【简答题】Singles Day falls on every November 11th, and as the name indicates, this relatively new holiday is one exclusively for people who are still living the single life. I was a bit surprised when I google...
【单选题】天然气是各种气体的混合物,其主要成分是各种碳氢化合物,其中( )占绝大多数,一般含量都在80%左右。
【简答题】大气是( )的混合物,主要成分是( ),此外还有含量不定的( )、( )微粒。
【简答题】The advanced materials mentioned in the pre-reading part of study are __________________, _______________________, _______________________________ and ___________________________________.
【简答题】阅读理解。 The ladies club always had a meeting every Friday afternoon and someone came to talk to them about important things. After that, they had tea and asked questions. One Friday, a man came and talk...
【简答题】For this part, you are allowed 35 minutes to write a composition on the topic: Reading Preferences. You should write at least 150 words, and base your composition on the table and the outline given be...