长轨列车在曲线半径为300m以下区段及侧向通过道岔时,限速()。 ["A.5km\/h","B.15km\/h","C.25km\/h","D.45km\/h"]
在完全竞争市场厂商的长期均衡产量上必然有:() ["A、MR=LMC≠SMC,式中MR=AR=P;","B、MR=LMC=SMC≠LAC,式中MR=AR=P;","C、MR=LMC=SMC=LAC≠SAC,式中MR=AR=P;","D、MR=LMC=SMC=LAC=SAC,式中MR=AR=P。"]
说明DK-1型电空制动系统中隔离二极管264的作用?
长轨列车在曲线半径为500m以下区段运行时,限速()。 ["A.5km\/h","B.15km\/h","C.25km\/h","D.45km\/h"]
关于胆囊的描述,正确的是() ["A、有储存和浓缩胆汁的功能","B、位于肝门处","C、有分泌胆汁的功能","D、胆囊体与腹前壁相接触"]
一切电话中断时,列车在自动闭塞区间运行应遵守哪些规定?