单项选择题
A.Evaporation B.Circulation C.Condensation D.Distillation
Which of the following can be used in hydraulic transmi...
单项选择题Which of the following can be used in hydraulic transmission system?（）
A.Hydraulic oil B.Animal oil C.Light oil D.Fuel oil
（） play a very important part in hydraulic systems by p...
单项选择题（） play a very important part in hydraulic systems by preventing interaction between different parts of the hydraulic circuit.
A.Motors B.Check valves C.Safety valves D.Reducing valve
Cargo handling unit is rated according to the （） to be ...
单项选择题Cargo handling unit is rated according to the （） to be lifted.
A.cargo crane B.jib C.safe working load D.oil pressure
