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【单选题】

矿物燃料、润滑油及有关原料进口金额占初级产品进口金额的大致比例为: ( )。

A.
1/2
B.
1/3
C.
1/4
D.
1/5
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参考答案:
参考解析:
.
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【单选题】测定润滑油机械杂质的苯废液应()。

A.
倒入水池中
B.
倒入封闭容器中,进行回收
C.
倒入废液罐中
D.
倒入废油中

【单选题】加注润滑油要加至()。

A.
油尺的下刻度线
B.
油尺的上刻度线
C.
上下刻度线的中间
D.
上刻度线以上1厘米

【单选题】All over Europe, and in North America, there’re lakes and forests which are dead or (71) and the (72) is thought to be acid rain. What is acid rain Mr. Justin Cook, a scientist, explains: "All fossil ...

A.
All over Europe, and in North America, there’re lakes and forests which are dead or (71) and the (72) is thought to be acid rain. What is acid rain Mr. Justin Cook, a scientist, explains: "All fossil fuels, (矿物燃料),that (73) oil, coal and gas, contain sulphur. When these are burnt, for example (74) motor vehicles, they form sulphuric acid (硫酸)This (75) UP into the air, and soon it falls back to (76) , into lakes and (77) trees in forests." This can cause many local problems. 78 a result, lakes become acidic, fish disappear and trees are killed. The pollution is carried great distances by the wind, so sulphuric acid (79) in Britain can travel as far as Scandinavia (斯堪的纳维亚). Czech is one of the countries with the most acid rains and large areas of (80) consist only (81) dead trees.
B.
Is there (82) that can be done about acid rain Mr. cook says: "The rain (83) of acid rain is (84) power stations to install filters that (85) the acid getting out into the air. Here in Britain, the only (86) that has been taken is that the chimneys are built (87) so that the pollution is more distributed." If the petrol used in motor vehicles (88) lead--free, then it Would be possible to filter exhaust fuses (废气) which are a (89) cause of pollution. But these filter mechanisms (机械装置)can not work (90) the leads is removed.

【多选题】给水泵润滑油进水的原因有()

A.
轴封漏汽进入轴承内
B.
冷油器内部泄漏
C.
油侧压力大于水侧压力