单项选择题
A fuse that blows often should be replaced only with a fuse of （）.
A.the recommended current and voltage rating B.higher current and voltage rating C.higher current and lower voltage rating D.lower current and higher voltage rating
单项选择题 A constant output voltage from an AC generator is maintained by the （）.
单项选择题 What type of rotor is used in split-phase motors?（）
单项选择题 The load sharing characteristics of two diesel generator operating in parallel are mostly dependent on their governor （）.
