多项选择题 Listen to the conversation. Which ideas do the speakers talk about? Check the ideas they all agreed to do. u15-1 A、replacing the light bulbs B、using solar energy C、eating cold food more often D、turning the computers off at night
判断题 棚车用以装运贵重和怕日晒雨淋的货物,不能在车内安装火炉、烟囱、床板等,不可以运送人员和牲畜。
单项选择题 当变极距式电容传感器的动极板受被测物体作用引起位移x时,两极板之间的距离d减小,从而使电容量() A、增大 B、减小 C、 不变 D、 不确定