变直径管，当直径d1=320mm时，流速v1=1.5m/s；当直径d2=160mm时，流速v2为
A. 3m/s
B. 4m/s
C. 6m/s
D. 9m/s
Have you decided ________for Australia?
A. when will you leave
B. when do you leave
C. you will leave when
D. when you will leave
Can you tell me _________ ?
A. where does Tom live
B. where Tom lived
C. Tom lives where
D. where Tom lives
The old man asked me ________ .
A. where was the cinema
B. where is the cinema
C. where the cinema was
D. where was the way to the cinema
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