单项选择题
A.usually B.commonly C.exceptional D.unavoidably
（） is a machine by which electrical energy is transform...
单项选择题（） is a machine by which electrical energy is transformed into mechanical energy.
A.An alternator B.An electric motor C.A diesel engine D.A main switchboard
（） shall be continuously powered and shall have an auto...
单项选择题（） shall be continuously powered and shall have an automatic changeover to a stand by power supply in case of loss of normal power supply.
A.Cooling system B.Alarm system C.The air conditioning installation D.The mooring equipment
The liquid flowing in the capillary is such that the di...
单项选择题The liquid flowing in the capillary is such that the difference in （） readings taken before the capillary and after it is related to the oil viscosity.
A.pressure B.velocity C.flow rate D.temperature
