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【单选题】
Rescue Platform In the aftermath of the terrorist attacks on the World Trade Center, security experts are trying to develop new ways of rescuing people from buming skysrapers. One idea is a platform. capable of flying vertically and hovering in the air like a helicopter. The platform. would rise up and down alongside a skyscraper and pick up people trapped in high stories. The idea for the vertical takeoff platform. was hatched more than ten years ago by a Russian aerospace engineer, David Metreveli, who has since moved to Israel. Metreveli's dedsign, called the Eagle, calls for two jet engines that turn four large horizontal propellers. The spinning of the propellers generates the necessary lift, or upward force, to raise the platform. The more power is supplied to the propellers, the higher the platform. rises. Moving the platform. sideways involves applying differing amounts of power to each propeller. Helicopters are now used in some cases to get people out of buming buildings, Escape baskets slung from them dangle beside the building for people to climb into. Unfortunately, the baskets cannot reach every floor of a building because the ropes from which they hang become unstable beyond a certain length. So far, Metreveli has built a small-scale model of the Eagle to test his idea. In the wake of September 11, he has been able to secure enough funding to start building a larger, 4-meter by 4-meter prototype, which he calls the Eaglet. A rescue platform. called the Eagle is capable of moving vertically but not sideways.
A.
Right
B.
Wrong
C.
Not mentioned
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举一反三
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A.
滴定速度和摇瓶速度的控制
B.
操作过程中容器的选择和使用
C.
共存干扰物的消除
D.
滴定过程中溶剂的选择
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A.
称量方式和称量速度昀控制
B.
用什么样的酸或碱控制反应条件
C.
用自身颜色变化,还是用专属指示剂或用外加指示剂确定滴定终点
D.
滴定过程中溶剂的选择
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A.
本报文发给所有台站“General Address”
B.
继续“Go ahead”
C.
索要地址“Give address”
D.
开始“Get afoot”
【简答题】go( ) 开始;继续
【多选题】在拟定氧化还原滴定滴定操作中,属于滴定操作应涉及的问题是()。
A.
称量方法和称量速度的控制
B.
用什么样的酸或碱控制反应条件
C.
用自身颜色变化,还是用专属指示剂或用外加指示剂确定滴定终点
D.
滴定过程中溶剂的选择
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A.
称量方式和称量速度的控制
B.
用什么样的酸或碱控制反应条件
C.
用自身颜色变化,还是用专属指示剂或用外加指示剂确定滴定终点
D.
滴定过程中溶剂的选择
【多选题】在拟定氧化还原滴定滴定操作中,属于滴定操作应涉及的问题是()
A.
滴定条件的选择和控制
B.
被测液酸碱度的控制
C.
滴定终点确定的方法
D.
滴定过程中溶剂的选择
【多选题】在拟定氧化还原滴定操作中,属于滴定操作应涉及的问题是( )
A.
滴定条件的选择和控制
B.
被测液酸碱度的控制
C.
滴定终点确定的方法
D.
滴定过程中溶剂的选择
【单选题】青少年鼻出血部位大多在:
A.
鼻腔上壁
B.
鼻腔下壁
C.
鼻前庭
D.
鼻腔外壁
E.
鼻中隔前下方
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