阅读理解。
Are some people born clever, and others born stupid? Or is intelligence(智力)developed by our
environment and our experience? Strangely enough,the answer to these questions is yes. To some
extent Our intelligence is given to US at birth,and no amount of education can make a genius (天才)
out of a child born with low intelligence. On the other hand,a child who lives in a boring environment
will develop his intelligence less than one who lives in rich and varied surrounding (环境). Thus the limits
of person' s intelligence are fixed at birth,whether or not he reaches those limits will depend on his
environment. This view, now held by most experts,can be supposed in a number of ways.
It is easy to show that intelligence is to some extent something we are born with. The closer the
blood relationship between two people,the closer they are likely to be intelligent. Thus if we take two
unrelated people at random from population, it is likely that their degree of intelligence will be completely
different. If, on the other hand,we take two identical twins,they will very likely to be as intelligent as
each other. Relations like brothers and sisters,parents and children, usually have similar intelligence,and
this clearly suggests that intelligence depends on birth.
Imagine now that we take two identical (完全相同的)twins and put them in different environments.
We might send one,for example,to a university and the other to a factory where the working is boring.
We would soon find differences in intelligence developing,and this shows that environment as well as
birth plays a part. This conclusion is also suggested by the fact that people who live in close contact
with each other, but who are not related at all are likely to have similar degree of intelligence.
1. If a child is born with low intelligence,he can ________.
A. become a genius
B. not reach his intelligence in his life
C. reach his intelligence limits in rich surroundings
D. still become a genius if he should be given special education
2. In the second paragraph,the underlined sentence means "if we _______."
A. pick any two persons
B. take out two different persons
C. choose two persons who are relative
D. choose two persons with different inteili2ence
3. The example of the twins going to a university and to a factory separately shows_______.
A. the part that birth plays
B. the importance of their positions
C. the importance of their intelligence
D. the role of environment on intelligence
4. The best title of the passage can be _________.
A. Surroundings
C. Dependence on Environment
B. Intelligence
D. Effect of Education
小灯泡正常发光时灯丝的电阻，小明同学设计了如图所示的实验电路，图中
为已知阻值的定值电阻。 
无示数，
有示数，若电路中只有一处故障，则电路的故障可能是_______________。
向_______端移动（填“左”或“右”），使电压表
，若此时电压表
，则小灯泡正常发光时灯丝电阻的测量值
=_________（用测量量和已知量的符号表示）。