影响调压器通过能力的因素有()。
A、阀孔的面积
B、阀门前后压力降
C、燃气性质
D、燃气温度
参考答案:A, B, C
Pre-entry refers to the ______ of Customs entry documents for an export consignment before it actually leave the country.
A.report
B.submission
C.issue
D.order
主油泵区别于辅助油泵、紧急油泵是()
A.流体介质
B.轴驱动方式
C.润滑方式