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【单选题】
一些科学家认为，奥尔特云（，Oort Cloud）是一个包围着太阳系的球体云团，约为半径1光年的球体，在某些意义下代表太阳系的大小；太阳可以视为半径70万km，密度约是水的1.4倍，即约1.4 （g/cm^3）。根据上述数据推算太阳系的密度。（可用计算器计算）A.
2*10^-15 (g/cm^3)
B.
2*10^-18 (g/cm^3)
C.
2*10^-21 (g/cm^3)
D.
2*10^-24 (g/cm^3)
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【单选题】According to the passage, Mr. Howard might agree that______.
A.
the claim of $54m is not absurd
B.
even a mad accuser deserve his day in court
C.
the rule of law results in more detailed rules for almost every problem
D.
the explosion of laws is not conducive to judging by one's sense
【单选题】According John Howard, it would be more important ______ in order to help the poor countries.
A.
for the rich countries to increase their overseas aids
B.
for the rich countries to raise their moral standards
C.
for the rich countries to remove tile trade barriers
D.
for the rich countries to increase their mean subsidies to poor overseas farmers
【单选题】According to Howard, background music
A.
can possibly give people better feelings.
B.
increases production by 4.5 percent in factories.
C.
is sometimes very boring for workers.
D.
is always faster than any other music.
【单选题】According to Howard Catton, why do more nurses tend to work in Australia?
A.
Because of attractive salaries and a series of incentives.
B.
Because of starting salaries and recruitment activity.
C.
Because of the convenient air travel between two countries.
D.
Because of the permanent residency and accommodation.
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