题型:选择题 The Tibetans have lived in the Himalayas for centuries and have adjusted to the conditions _______.[ ]A. at such great height B. at such a great height C. on such great height D. on such a great height 查看答案
题型:单项选择题 关于船舶电网,下列说法错误的是()。A.动力电网主要向电动机和照明负载供电B.应急电网是在主电网失电后,向全船重要的辅机、应急照明信号灯、通信导航等设备供电C.小应急照明是由蓄电池组供电D.弱电网是向全船无线通信设备、助航设备、报警系统供电 查看答案