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问题 解答题

我国的淡水鱼类大约有700种，比海洋鱼类少65%．我国的海洋鱼类大约有多少种？

答案

700÷（1-65%），

=700÷0.35，

=2000（种）；

答：我国的海洋鱼类大约有2000种．

单项选择题

The cost baseline has all of the following characteristics EXCEPT:

A) It is a time-phased budget that will be used to measure and monitor cost performance on the project.
B) It shows the actual cost expenditures throughout the life of the project.
C) It is developed by summing estimated costs by period.
D) It is usually displayed in the form of an S-curve.
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单项选择题

跨局旅游列车的车次范围是（）次。

A.Y1～Y098

B.Y1～Y198

C.Y1～Y298

D.Y1～Y498
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