光伏发电站并网点频率在()范围内应能连续运行。 ["49.0Hz~51.0Hz","49.3Hz~50.2Hz","49.5Hz~50.2Hz","49.7Hz~50.2Hz"]
钢筋混凝土结构中钢筋作用是承受()。 ["压力或拉力","容许应力","强度","极限强度"]
诗句“天子呼来不上船,自称臣是酒中仙”形容的是()。 ["苏轼","李白","杜甫","白居易"]
冬季施工混凝土如单从温度方面考虑最好采用哪种运输机械()。 ["手推车","输送泵","输送带","翻斗车"]
诗句“何以解忧?唯有杜康”的作者是()。 ["苏轼","李白","曹操","刘邦"]
进行接触网停电作业时如何防止作业人员误登误入有电设备?