投入并联的各台发电机的最大功率与最小功率之比应不超过( )。
A. 2:1
B. 4:1
C. 3:1
D. 3:2
查看答案
The car is quite ______ of petrol.
A. economic
B. economical
C. saving
D. sparing
______ being late made the boss angry.
A. Him
B. His
C. He's
D. For him
在初步设计时,柴油发电机组的容量通常按变压器容量的( )考虑,但实际上能否满足使用要求却很难肯定。
A. 8%~10%
B. 10%~30%
C. 20%~50%
D. 10%~20%
72()
A. include
B. keeps
C. make
D. increase