流体流动形态用＿＿＿＿＿来判断，当＿＿＿＿＿时为瑞流，当＿＿＿＿＿时为滞流，当＿＿＿＿＿时为过渡流。
流体在等直径的导管中作稳态流动时，由于流动有摩擦阻力损失，因此流体的流速沿管长而逐渐变小。（ ）
A. 对
B. 错
Which is another word for quotation mark?
A. inverted comma
B. quotation sign
C. speech mark
If a word that's too long to fit on a line is broken into two parts, the first part ends with.
A. an ellipsis mark
B. a backslash
C. a hyphen
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