离心泵启动前,一定要向蜗壳内充满水以后方可启动,否则将造成泵体发热振动而造成. 发布时间:2017-09-17 08:23 │ 来源:www.tikuol.com 题型:填空题 问题: 离心泵启动前,一定要向蜗壳内充满水以后方可启动,否则将造成泵体发热振动而造成.
题型:填空题 With the nuclear crisis worsening in Iran, the world’s attention is fixed again on ________is called the Middle East.A.whichB.whatC.thatD.it 查看答案