风管制作安装的工程量如何计算？
注水井分层测试的方法有（）。 ["机械式压力计测试和电子压力计测试","井下流量计测试和投球测试","投球测试和电子压力计测试","井下流量计测试和电子压力计测试"]
气泡病原因是什么？
One of the main differences between the various types of screw pumps is in the （）. ["stuffing box diameter","direction of rotation of the screws","pitch of the screws","type of driving gear"]
光端机接口板是什么？
“文明交通行动计划”是由哪两个部委联合发文？从何时开始正式启动实施？计划实施多长时间？
