A.60
B.120
C.180
D.360
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A.copper and antimony
B.steel and babbitt
C.aluminum or beryllium alloy
D.zinc or an alloy of tin and lead
A.prevent grounds in branch circuits
B.prevent opens in motor circuits
C.permit momentary overloads without melting
D.guard lighting and electronic circuits
A.Each has three separate but identical armature windings acted on by one system of rotating magnets
B.Each has one armature winding acted on by three identical but separate systems of rotating magnets
C.All three-phase alternators are designed to operate with a O8 leading power factor
D.The three phases always provide power to the load through three sets of slip rings and brushes
A.eliminate slippage
B.provide excitation
C.provide starting torque
D.increase efficiency
A.wash it with fresh water and apply an external source of heat
B.renew the windings
C.send it ashore to an approved service facility
D.rinse all electrical parts with a carbon tetrachloride cleaning solvent and then blow dry the motor with compressed air
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