Questions 22 to 25 are based on the passage you have just heard.
A. They have to live in dormitories of other universities.
B. They have to share dormitories with more roommates.
C. They have to live off campus.
D. They have to exchange dormitories with freshmen.
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Questions 19 to 21 are based on the passage you have just heard.
A. Trains are more environmentally friendly than trucks.
B. Trains can transport more goods than trucks do.
C. Freight trains have an accident rate that is only 1/2 that of the trucking industry
D. Railroading does not wear out highways at all.
Questions 9 to 11 are based on the conversation you have just heard.
A. Stimulating students to try new things.
B. Letting students learn as much as they can.
C. Teaching through interesting activities.
D. Asking students to write whatever they like.
Questions 12 to 15 are based on the conversation you have just heard.
A. When the reason is obvious.
B. When the behavior could have negative effects.
C. When people"s behavior is illegal.
D. When the behavior is unexpected.
(2007年)层流沿程阻力系数λ( )。
A. 只与雷诺数有关
B. 只与相对粗糙度有关
C. 只与流程长度和水力半径有关
D. 既与雷诺数有关又与相对粗糙度有关
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