单项选择题
A.Accommodation heating system
B.Steering gear
C.Boiler control
D.Cargo control
单项选择题 The operation of （） two alternators requires the voltages to be equal and also in phase.
单项选择题 With a purely （） load the voltage and current are in phase, giving a power factor of one.
单项选择题 The separate supplies are connected in either star or delta formationThe star formation is most commonly used and requires（） slip-rings on the alternator.