单项选择题
The efficiency of a flash type evaporator can be increased by（）
A.lowering brine discharge density B.decreasing the absolute pressure of each stage C.increasing the saltwater feed heater temperature D.increasing the pressure at the spray pipe
单项选择题 In some modern large diesel engines, which of the following is used as the support for the main bearings?（）
单项选择题 Valve lash, or clearance refers to the （）
单项选择题 Auxiliary diesel engines can be automatically shut down as a result of （）
