The next decade could see commuters speeding to work at about 300 miles per hour aboard magnetic levitation vehicles, according

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问题     The next decade could see commuters speeding to work at about 300 miles per hour aboard magnetic levitation vehicles, according to a report by Argonne National Laboratories. But before "maglev" vehicles can become commercial successes, the report says, people need to stop thinking of them as high-speed trains.  Instead, consider them low-flying aircraft. Argonne contends that maglev vehicles will be best suited to replace commuter aircraft. Plane flights under 600 miles are the least energy-efficient, and maglev "planes" should cut these fuel needs by up to 75 percent. Reportedly, the money saved by a 2,000 mile maglev network linking major cities world more than pay for its construction in 20 years. The quiet purr of levitating crafts would also be a balm for neighborhoods tormented by the roar of conventional takeoffs and landings. The technology behind magnetic levitation is already well understood, the report notes. The west Germans and the Japanese already well understood, the report notes. The West Germans and the Japanese have several full-scale working models. Meanwhile, research in the United States has lapsed.  
Which countries have probably spent the most money on maglev research?

选项 A、France and West Germany.
B、Japan and West Germany.
C、the United States and Japan.
D、West Germany and the United States.

答案B

解析 最后两句提到联邦德国和日本已有几个实际运作模型,而美国在这方面的研究落后了,可见联邦德国和日本花钱最多。
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