流体流动时，质点相互混杂、流线紊乱的流动称为紊流。
参考答案：对
The first recorded use of natural gas to light street lamps it was in the town of Frederick, New York, in 1825.
A．was
B．is
C．it is
D．were
燃气轮机1＃，2＃，3＃轴承是什么型式的？
