单选题吊杆按结构和使用形式不同可分为() ①轻型单吊杆; ②轻型双吊杆; ③普通重型吊杆; ④“V”型重吊; ⑤重型双吊杆。A①②④⑤B①②③⑤C①~④D②~⑤
单选题
吊杆按结构和使用形式不同可分为() ①轻型单吊杆; ②轻型双吊杆; ③普通重型吊杆; ④“V”型重吊; ⑤重型双吊杆。
A
①②④⑤
B
①②③⑤
C
①~④
D
②~⑤
参考解析
解析:
暂无解析
相关考题:
单选题If the thermal bulb of an expansion valve is incorrectly placed at the center of the coil instead of the end, it will ().Aincrease the capacity of the coilBincrease the superheat at the bulbCdeliver more refrigerant to the coilDdecrease the capacity of the coil
单选题海船规则条款不妨碍各国政府为军舰及护航下的船舶所制定的关于额外的(),或者为结队从事捕鱼的渔船所制定的关于额外的队形灯、信号灯或号型的任何特殊规定的实施。 ①队形灯; ②信号灯; ③号型; ④笛号A①③④B①②③④C②③④D①②④
单选题If any cargo is damaged,the insurance company usually pays to the cargo owner a sum of money equal to the value of().Athe cargoBthe cargo damagedCthe cargo minus the franchiseDthe cargo damaged minus the franchise
单选题Which of the devices listed, when used on an electro-hydraulic steering gear, keeps the movement of the redder closely in step with the steering wheel?()AThe follow-up gearBThe rudder angle indicatorCThe synchronous electric transmitterDA rudder angle limit switch
单选题If a line at right angles to the axis rotates about that axis and, at the same time, moves parallel to the axis, it will generate ().Aa helixBa helicoidalCa curveDa cone
单选题锅炉的效率是同一时间内()。A蒸发炉水的汽化潜热/消耗燃料的发热量B蒸发炉水的汽化潜热/烟气传给受热面的热量C工质得到的有效热量/烟气传给受热面热量D工质得到的有效热量/消耗燃料的发热量
单选题天文定位所需用的天体高度应是()。A天体视方向与视地平之间的垂直夹角B天体真方向与视地平之间的垂直夹角C天体中心与测者地心真地平之间在天体垂直圈上所夹的弧距D天体上、下边沿与测者地面真地平之间在天体垂直圈上所夹的弧距
单选题There is a danger of the starting current that the windings are burnt out()Ato increaseBto be so increasedCincreasedDbeing so increased
单选题Large pipes or () are fitted between the steam and water drums to ensure good natural circulation of water.Afire-tubesBfurnacesCdown-comersDsoot-blowers
单选题在大风浪中航行,为防止主机可能发生故障,应()。A主机降速运行防止飞车B加大气缸注油量以提高主机发出功率C关小海底吸入阀以免吸空D加大冷却水流量以提高冷却效果