题目内容
业主在项目的整个实施过程中有不同的称谓,下列中不属于其称谓的是()。
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听力原文： The world’s first completely automatic railway has been built under the busy streets of London. The railway is called the Victoria Line, and it is part of the complete London underground railway.
The new Victoria Line was opened in 1969. This new line was very different from the others.
The stations on the other lines need a lot of workers to sell tickets, and to check and to collect them when people leave the trains. This is all different of the Victoria Line. Here a machine checks and collects the tickets, and there are no workers on the platforms.
On the train, there is only one worker. If necessary, this man can drive the train. But usually he just starts it; it runs and stops by itself. The trains are controlled by electrical signals which are sent by the so-called "command spots". The command spots are the same distance apart. Each sends a certain signal. The train always moves at the speed that the command spots allow. If the command spot sends no signals, the train will stop.
Most of the control work is done by computers. The computers also fix the train’s speeds, and send the signals to the command spots.
Other machines make sure that the trains are always a safe distance apart. If one train stays too long at a station, the other trains will then automatically move slower. So there is no danger of accidents on the line.
What happened to the London underground railway about three decades ago？
粉尘对人体的危害程度与其理化性质有关,与其生物学作用及防尘措施等也有密切关系。在卫生学上,常用的粉尘理化性质包括粉尘的化学成分、分散度、溶解度、密度、形状、硬度、荷电性和爆炸性等。下列各选项中有关一些生产粉尘的理化性质说法不正确的是()。
某随机事件最多只有X、Y、Z三种互不相同的结果,关于X、Y、Z发生的概率,以下有可能的是________。
直接比较是以待估土地的状况为基准,把各交易案例与其逐项比较,然后将比较的结果转化为()。
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