6月5日是世界环境日，空气的净化问题正日益受到人们的关注。属于空气污染物是
A．甲烷、二氧化碳、氢气
B．二氧化碳、氯化氢、氮气
C．二氧化硫、一氧化碳、二氧化氮
D．二氧化硫、氮气、氧气
答案：C
根据空气污染状况来分析本题，知道造成空气污染物质有二氧化硫、氮氧化物、一氧化碳和可吸入颗粒等，空气污染主要是粉尘和气体，有害气体有一氧化碳、二氧化氮、二氧化硫。
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| Look 1 this girl. 2 name is Ann. She is twelve. Mike is her brother. He is 3 Class Three, Grade One. Do you know how old he is? He is fourteen years old. The brother 4 sister are in the same school-No.2 Middle School. 5 mother is a teacher. she is an 6 teacher. Their father is a teacher, 7 . He is a Chinese teacher in Guangming Middle School. Their students all love them because they love their students. They 8 a cat. 9 Name is Mimi. It is a nice cat, The cat and Ann are 10 friends. |
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