B) new discoveries are less likely to occur in social sciences
C) it is based on a fairly representative quantity of date
D) the records of social systems are more reliable
34. The chances of the physical sciences being subject to great changes are the biggest because _______.
A) contradictory theories keep emerging all the time
B) new information is constantly coming in
C) the direction of their development is difficult to predict
D) our knowledge of the physical world is inaccurate
35. We know less about the astronomical universe than we do about any social system because _______
A) theories of it origin and history are varied
B) our knowledge of it is highly insecure
C) only a very small sample of it has been observed
D) few scientists are involved in the stud of astronomy
Questions 36 to 40 are based on the following passage:
In the early days of nuclear power, the United States made money on it. But today opponents have so complicated its development that no nuclear plants have been ordered or built here in 12 years.
The greatest fear of nuclear power opponents has always been a reactor "meltdown". Today , the chances of a meltdown that would threaten U. S. public health are very little. But to even further reduce the possibility, engineers are testing new reactors that rely not on human judgement to shut them down but on the laws of nature. Now General Electric is already building two advanced reactors in Japan. But don’ t expect them ever on U. S. shores unless things change in Washington.
The procedure for licensing nuclear power plants is a bad dream. Any time during, or even after, construction, an objection by any group or individual can bring everything to a halt while the matter is investigated or taken to court. Meanwhile, the builder must add nice-but-not-necessary improvements, some of which force him to knock down walls and start over. In every I case where a plant has been opposed, the Nuclear Regulation Commission has ultimately granted a license to construct or operate. But the victory often costs so much that the utility ends up abandoning the plant anyway.
