油液在管道的速度是不一样的，所以我们一般用平均速度来衡量油液的速度，关于这个平均流速说法错的是（）
A. 平均流速不是瞬时流速，而是瞬时流速的平均值
B. 计算公式为v=q/A
C. 平均流速与油液的流量成正比
D. 平均流速与管路的通流面积成正比
查看答案
Which one of the following ststements is not true?
A. Most of Henry's stories are set in the early 20th century.
B. Many ofHenry's stories take place in New York City.
C. Many ofHenry's stories deal for the most part with ordinary people.
D. Henry's stories are known for their surprise beginnings.
Which one of the following is not O. Henry's writing style?
A. ingenious plot
B. twist ending
C. vivid characterization
D. beautiful description
在设计流量下，污水在管道中的水深与管道直径的比值称为。
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