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问题 单项选择题

下列不属于气井产出的非地层水的是（）

A、凝析水

B、钻井液

C、矿层水

D、外来水

答案

参考答案：C

解答题

在甲，乙，丙，丁四个培养皿内分别放两张吸水纸，在将相同数量的大豆种放在上面，在不同的条件下进行培养．数日后记录的种子发芽的情况如下表：

装置甲乙丙丁
场所日光下日光下黑暗中黑暗中
温度23℃23℃23℃23℃
吸水纸干湿状态潮湿干燥潮湿干燥
数日后种子发芽情况全部发芽没有发芽全部发芽没有发芽
（1）本实验可以得出种子萌发所必需的一个环境条件是______．

（2）种子的萌发除了环境条件外，还需要一定的自身条件，即胚必须是完整、成活的，而且是______的．

（3）若要证明光照对种子萌发的是否有影响，在实验设计上可选用上表中的______两个装置作为一组对照实验来进行探究．根据上表中记录的情况，你认为大豆种子的萌发是否受光照的影响？______．
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单项选择题


Directions: There are 10 blanks in the following passage. For each numbered blank, there are 4 choices marked A, B, C and D.

It is difficult to imagine what life would be like without memory. The meanings of thousands of everyday perceptions, the bases (51) the decisions we make, and the roots of our habits and skills are to be (52) in our past experiences, which are brought into the present (53) memory.
Memory can be defined as the capacity to keep (54) available for later use. It includes not only "remembering" things like arithmetic or historical facts, but also any change in the way an animal typically behaves. Memory is (55) when a rat gives up eating grain because he has sniffed something suspicious in the grain pile. Memory is also involved when a six-year-old child learns to swing a baseball bat.
Memory (56) not only in humans and animals but also in some physical objects and machines. Computers, for example, contain devices for storing data for later use. It is interesting to compare the memory-storage capacity of a computer (57) that of a human being. The in stant-access memory of a large computer may hold up to 100 000 "words" —ready for (58) use. An average American teenager probably recognizes the meanings of about 100 000 words of English. However, this is but a fraction of the total (59) of information which the teenager has stored. Consider, for example, the number of facts and places that the teenager can recognize on sight. The use of words is the basis of the advanced problem-solving intelligence of human beings. A large part of a person’s memory is in terms of words and (60) of words.

A．to

B．with

C．against

D．for
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