问题
单项选择题
在空气污染物检测中，悬浮颗粒物中能用鼻和嘴吸入的那部分颗粒物称为（）
A.呼吸性颗粒物
B.可吸入颗粒物
C.胸部颗粒物
D.细颗粒物
E.粗颗粒物
答案
参考答案：B
解析：颗粒物按其粒径大小不同，具有不同的性能，总的原则是粒径越小，进入呼吸道越深。
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在空气污染物检测中，悬浮颗粒物中能用鼻和嘴吸入的那部分颗粒物称为（）
A.呼吸性颗粒物
B.可吸入颗粒物
C.胸部颗粒物
D.细颗粒物
E.粗颗粒物
参考答案：B
解析：颗粒物按其粒径大小不同，具有不同的性能，总的原则是粒径越小，进入呼吸道越深。
The little boy entered the house unhappily. His mother was 1 cakes in the kitchen. She smiled as she 2 ,but stopped when she saw his face.“Tyler, 3 happened? Is everything okay?” “Nothing is okay,Mom,” said the boy.” Today, in our science lesson, Mrs Green talked about the 4 .The whole world is getting dirtier and many animals and plants are dying, She wants us to think of something we can do to help. I thought all the way home, but there is 5 I can do to make a difference.” “Let me tell you a 6 ,”the mother said after thinking for a while .“ One morning a man was walking down a beach, there he saw thousands of dying starfish（海星） covering the beach, they were pushed up by the 7 . and it was too far for them to make their way back by 8 . The man shook his head as he walked along,“What a pity!So many starfish will die on the beach.” The man felt very 9 for those starfish . He went on walking and just at that time he was 10 to find a boy in front who was throwing the starfish back into the sea as 11 as he could. “How silly you are! My 12 ,” the man said.“There are so many starfish, and can you throw all of them back?” The boy didn’t stop but kept throwing. “ 13 I can’t help them all, I can make a difference to this one, and this one, and this one,”said the boy.“Thinking for a moment, the man 14 to help return the starfish to their home. He smiled and said to himself, “Sometimes the biggest lesson in life comes from the 15 person.”
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