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问题 填空题

已知一电流表的满偏电流为3mA，其内阻为120Ω，要把它改装成量程为6V的电压表应______联（串联还是并联）的电阻值R=______．若将其改装量程为3A的电流表，应当对原电流表______联（串联还是并联）的电阻值R=______．

答案

改装成电压表要串联电阻分压串阻值为：

R=

U
Ig
-Rg=
6
0.003
-120=1880Ω

改装成电流表要并联电阻分流，并联电阻阻值为：

R=

IgRg
I-Ig
=
0.003×120
3-0.003
≈0.12Ω

故答案为：串，1880，并，0.12．

单项选择题

保荐人应当自持续督导工作结束后（）个工作日内向（）报送“保荐总结报告书”。

A．10；中国证监会和证券交易所

B．15；证券交易所

C．15；中国证监会和证券交易所

D．15；中国证监会
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单项选择题

Looking back on my childhood, I am convinced (1) naturalists are born and not made. Although we were all brought (2) in the same way, my brothers and sisters soon gave up their pressed flowers and insects. (3) them, I had no ear (4) music and languages, I was not an early reader and I could not do mental arithmetic.Before World War I we (5) our summer holidays in Hungary. I have only the memory of the house we lived (6) , of my room and my toys. I can hardly (7) clearly the large family of grandparents, aunts, uncles and cousins who gathered (8) door. But I do have a clear memory of the dogs, the farm (9) , the local birds and, (10) all, the insects.I am a (11) , not a scientist. I have a p (12) of the natural world, and my enthusiasm has led me into varied investigation. I love discussing my favorite topics and enjoy (13)  the midnight oil  (14)  reading about other people’s observations and discoveries. Then  (15)  happens that brings these observations together  (16)  my conscious mind. Suddenly you fancy (想象), you see the answer  (17)  the riddle, and books, of which some might honor with the title of scientific research.But curiosity, a keen eye, a good memory and enjoyment of the animal and plant world do not make a scientist; one of the outstanding and essential  (18)  required is self-discipline, a quality I lack. A scientist requires not only  (19)  but also hard training, determination and a goal. A scientist, up to a point, can be made. A naturalist is  (20) . If you can combine the two, you get the best of both worlds.

第（5）空应选择（）

A．spent

B．purchased

C．wounded

D．burnt
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