在通信设备中的直流电流电源绝大多数由交流电转换而来。
在总需求与总供给的短期均衡中,总需求减少会引起() ["国民收入增加,价格水平上升","国民收入增加,价格水平下降","国民收入减少,价格水平上升","国民收入减少,价格水平下降"]
最早出现于经济发达的西方,距今大约有()多年的历史。
《汽车加油加气站设计与施工规范》规定:分离缓冲罐及容积大于0.3m3的排气缓冲罐,应设()。 ["压力表","液位计","温度计","安全阀"]
Which statements about inheritance are true?() [" In Java programming language only allows single inheritance."," In Java programming language allows a class to implement only one interface."," In Java programming language a class cannot extend a class and implement a interface together."," In Java programming language single inheritance makes code more reliable."]
某仓库新进的一批设备需要摆码,第一天摆码了600件,正好是60%,还有多少件未摆码完?