主扇风量为25000m3/min，通风阻力应小于（）Pa。 A.3920 B.250_爱下问搜题

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问题单项选择题

主扇风量为25000m³/min，通风阻力应小于（）Pa。

A.3920

B.2500

C.2940

D.4930

答案

参考答案：A

完形填空

完形填空。

     Tom is from Canada. He is twelve  1 . Now he is in Beijing Ren'ai International  2 . He is in  3 , Grade
Seven.  4 phone number is (010) 9758-6296. Minmin is  5 China. Her  6 name is Ann. She is twelve,  7 .
8 phone number is (010) 9272-5322. They are not in the same  9 ,  10 they are good friends. They like
their (他们的) school.

( )1. A. year old
( )2. A. School
( )3. A. class 4
( )4. A. Her
( )5. A. in
( )6. A. England
( )7. A. too
( )8. A. His
( )9. A. class
( )10. A. and

B. years old
B. school
B. Class four
B. His
B. from
B. Chinese
B. two
B. Her
B. classes
B. but

C. year olds
C. schools
C. Class Four
C. He
C. at (在)
C. English
C. to
C. She
C. schools
C. then (那么)

选择题

沙漠狐的耳朵很大，有利于散热，而北极狐的很小，毛也很多，有利于保温。导致它们形体差别的最重要因此，你认为是[ ]

A．阳光

B．水分

C．空气

D．温度