Прочитайте текст и выполните задания Engineers of the Imagination 1. U.S. physicist Richard Feynman ...: ответ на тест 1077997 - Английский язык

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Engineers of the Imagination
1. U.S. physicist Richard Feynman first suggested the idea for nanomachines in 1959. He had given a lecture on the possibility of building devices atom by atom. Eric Drexler, another physicist, developed the idea. Beginning in 1977, Drexler wrote a series of books about nanoengineering. It was a great idea, but no one knew how to move individual atoms and put them in place. Engineers have not yet created practical nanomachines. They have developed micromachines. They have microscopic gears, wheels, and axles. These machines are no larger than a speck of dust.
2. Engineers at the U.S. Department of Energy’s Sandia National Laboratories in Albuquerque, New Mexico, have created a micromachine that has gears. Each one is smaller in diameter than a human hair. Making a tiny engine powerful enough to run one of these machines is a much more complicated problem. In 1988 engineers at the University of California – Berkeley created the world’s first micromotor. It was just 100 microns (100,000 nanometers) across. The motor was powered by static electricity. This energy made tiny gears spin at high speeds, but it wasn’t powerful enough to do any useful work.
3. Manufacturers may be able to produce these engines very cheaply, perhaps for only ten or fifteen dollars each. In 2003 Dr. Alex Zettl, a physicist at the University of California – Berkeley created the first nanomotor. It is a tiny electric motor so small that it can fit on the back of a cold virus. About two hundred of them could fit on a human hair. So far, all the motor can do is spin a tiny rotor. It has not produced enough power to run a machine. Engineers are certain, however, that they will soon develop much more powerful electric nanomotors.
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The main problem in creating nanomachines is …