断路器操作机构动作电压应满足:低于额定电压的()时不动作;高于额定电压的()时可靠动作。
参考答案:30%;65%
.The modern city was only a small fishing village compared to ____ it is now.
A which B that C what D where
钢进行扩散退火的目的是为了()、铸件或锻坯的化学成分和组织的不均匀性,进行再结晶退火的目的是为了(),便于继续冷加工。