燃油系统靠什么来加热（） A.液压油 B.空气 C.滑油 D.电源
题型：单项选择题
问题：
燃油系统靠什么来加热（）
A.液压油
B.空气
C.滑油
D.电源
题型：单项选择题
实验室用H2O2溶液和MnO2固体混合物制取O2，回答下列问题
（1）小明设计了如图所示的制取装置，发生反应的化学方程式是： ，装置中用注射器代替长颈漏斗的优点是 。（答一条）
（2）同组的小刚想从反应后的混合物中分离出MnO2固体，其主要操作是 ，此操作中必须用到的玻璃仪器是 。
燃油系统靠什么来加热（）
A.液压油
B.空气
C.滑油
D.电源
36 , and it is better to call a spade a spade. But dustmen can be as 37 as people of any other occupation, though we must 38 that their job is not a 39 one in the world. We often take dustmen for granted. Perhaps because they usually come very early in the morning, before most people are 40 .We are likely to forget their 41 .Our dustbins are 42 regularly, but we 43 stop to think about the men who do this. However, it is one of the most important jobs in the world, and when there are no dustmen to 44 the rubbish, the general 45 soon becomes aware that something is wrong. Recently, the dustmen of England went on strike for higher wages. 
e hills of rubbish around their dustbins, and they looked for other places in which to 50 it. Even Leicester Square, in the heart of West End of London, was 51 high with plastic bags full of smelly rubbish. This was a（n） 52 attraction that the people of London were not at all 53 to see. Even when the strike was over, it took several weeks for the country to get cleaned up completely. Perhaps now the English people appreciate the work of 54 dustmen rather 
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