【单选题】链条葫芦不得超负荷使用,起重能力在()以下的,允许一人拉链?
【简答题】Science can now account for many things which were thought to be ________ by ancient people. (mystery)
【判断题】只有损失机会而无获利可能的风险称为投机风险。( )
【单选题】Science can now ________ many things which were thought to be mysterious by ancient people.A) B) C) √D)
【单选题】Science can now ________ many things which were thought to be mysterious by ancient people.
【判断题】链条葫芦不得超负荷使用,起重能力在5t以下的允许2人拉链,不得随意增加人数猛拉。操作链条葫芦时,人员不准站在链条葫芦的正下方。
【单选题】链条葫芦不得超负荷使用,起重能力在5t以下的允许()人拉链,不得随意增加人数猛拉。