单项选择题
A.reciprocating B.hydraulic C.turbine D.vane
Domestic water pump is started automatically by （） whic...
单项选择题Domestic water pump is started automatically by （） which operates as the water level falls to a predetermined level.
A.a level controller B.a temperature switch C.a pressure switch D.a floating ball
In cargo crane, （） for lifting the load.A.a hoisting mo...
单项选择题In cargo crane, （） for lifting the load.
A.a hoisting motor B.a luffing motor C.a mooring motor D.a slewing motor
Manually operated band brakes may be fitted and （） will...
单项选择题Manually operated band brakes may be fitted and （） will have a brake arranged to fail-safe.
A.the drive pump B.the drive motor C.the warp end D.the purchase
