aruuuukaa12
06.06.2021 12:58

XI. Прочитайте текст. Выберите предложения, соответствующие его содержанию. Используйте T (true) – соответствует; F (false) – не соответствует

A Wonder Metal

The story of titanium is extraordinary. To begin with, it was discovered twice. A British scientist, William Gregor, found it first and called it menachanite, and six years later, in 1797, M.H. Klaproth, a German chemist, also found it and gave it its present name.

For many years, titanium was of inretest only to research chemists – it was considered too brittle1 to be of any practical value. Yet it was the impurities2 with which it was usually associated (it forms compounds easily with nearly every known element) that made it brittle.

It cost the chemists in many countries endless efforts to isolate pure titanium and even more to start producing it commercially. In 1948 the world stock of pure titanium was only ten tons. Today the output is much larger.

Titanium has one surprising property – it is completely inert in biological media, something the medical community was quick to notice. It is being used to make artificial joints3 and many other things necessary in surgery at the Priorov Central Institute of Traumatology and Orthopedics. Titanium instruments do not corrode, and are thirty per cent lighter than instruments made of stainless steel.

Titanium’s high standard of corrosion resistance, lightness, tensile strength4, and the ease of forging, rolling and stamping are finding it more and more uses. Titanium alloys are very useful in mechanical engineering, and for chemical and refectory5 apparatus. Titanium helped Soviet design engineers to surmount the sound and heat barriers in supersonic and high-altitude aircraft designing. On earth, it shows good work at chemical plants, in the pulp-and-paper and food industries. Moreover, it is still a source of surprise for the investigator.

Notes:

1brittle – хрупкий

2impurities - примеси

3 artificial joints - искусственные суставы

4 tensile strength – прочность на разрыв

5refractory – огнеупорный

41. Titanium, to say, was discovered twice.

42. Its present name this metal was given at the end of the 18th century.

43. Titanium was always considered to be of great practical value

44. It was the impurities that made titanium brittle.

45. It took the chemists great efforts to start commercial production.

46. Only some years ago the world stock of pure titanium was about 10 tons.

47. Titanium is very active in biological media.

48. Titanium items are much lighter than those made of stainless steel.

49. Owing its majestic properties titanium is used more and more widely.

50. Titanium alloys are not produced at industrial scale.

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Ответ:
keksukYT
28.04.2022 13:30
1) просто везде слово "will" и сам глагол (в утвердительных)
в отрицательных will not и сам глагол
2) 1- I shalln't send a letter to my friend next week
     who shal send a letter to my friend next week?
     when i shall send a letter to my friend?
     what shall i do next week &  
     2- they willn't go to the cinema tomorrow
          who will not go to the cinema tomorrow ?
           where will they go tomorrow ?
            when will they go to the cinema ?
     3- her father will not work at a shoe factory in a month
          whose father will not work at a shoe factory in a  month
           
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Ответ:
Arse20
28.04.2022 13:30
There's fun in the summer, but for half of the day fed up with it.Tsarina I now associated with something magical.There's a beautiful golden gates, as in the old TV show "In the animal world," only with more arms. At the entrance stands a saleswoman ice cream. Necessarily need to buy ice cream - it's like a ticket to a fairy tale, it is not without that experience. And straight to the singing fountain. There is a large park with squirrels, swans and ducks. Swans itself is fabulous. Yet in the middle of the lake there is an island with lush tree-like Lukomorie. It was a working day, so in the park there were few people and it was quiet, and the weather is great. Good then get a photo in the orange light of sunset.
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