关于抛射剂叙述错误的是（） A.抛射剂可分为压缩气体与液化气体_爱下问搜题

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问题单项选择题 A1/A2型题

关于抛射剂叙述错误的是（）

A.抛射剂可分为压缩气体与液化气体

B.气雾剂喷雾粒子大小、干湿与抛射剂用量无关

C.抛射剂在气雾剂中起动力作用

D.抛射剂可兼作药物的溶剂或稀释剂

E.压缩气体常用于喷雾剂

答案

参考答案：A

解析：抛射剂是喷射药物的动力，有时兼有药物的溶剂作用。抛射剂一般可分为氟氯烷烃、碳氢化合物及压缩气体三类。所以答案为A。

解答题

用指定的方法解下列方程；

（1）x²-4=0（因式分解法）

（2）x²-4x+3=0（配方法）

（3）3x²-2x-1=0（公式法）

（4）x²-5x+6=0．

完形填空

As far back as I can remember, I’ve always known that my brother was different. At first I thought this was a  31   thing. But when I got older I learned the truth. My brother had autism (孤独症) and Attention Deficit Disorder (儿童多动症) — serious  32   conditions. At 15, he  33   like a 7-year-old child. When he was little, I didn’t  34   it as much. But as he got older, it became more obvious. When something didn’t go his  35 , he got angry and it took hours to  36   him down. He would talk to himself and play with string. We could never  37   to give him his medicine, otherwise he’d go wild. I was always  38   when we took him anywhere, and I never wanted to bring any of my friends  39   with me.
When I was 10, I felt like I couldn’t  40   it any more. I’d shout at him for being different and would ask  41   he couldn’t be normal. Of course, he had no  42   what I was talking about. It became very hard,  43   when a friend of mine didn’t want to come over  44   her mom had said my brother was dangerous. Our fights  45   up until one day he came up to me. He gave me a big  46 , like he was saying, “I don’t know what I did  47 , but I hope you still love me.” At that moment I realized that I’d better learn to  48   him.
As I’ve gotten older, I’ve learned how  49   I really am. Having him as a brother has made me kinder and more patient. No matter how busy my  50   is, he’ll always listen to my problems. I worry about his future, but I know he’ll always be loved.

A．discouraged

A．experienced

A．embarrassed

D．comfortable