Прочитайте текст Steel copper and aluminium are used in making engineering products. Steel is a grey...: ответ на тест 607569 - Английский язык

Прочитайте текст
Steel, copper and aluminium are used in making engineering products.
Steel is a grey plastic material. It is heavier than aluminium but it is the hardest and the strongest of these three metals.
Copper is a red metal. It is harder and stronger than aluminium and more flexible than steel. But copper is the heaviest and the most expensive metal. The lightest and the most flexible of these materials is aluminium. It is a white hard metal.
Ответьте на вопрос
What kind of metal is aluminium?

Прочитайте текст
Steel, copper and aluminium are used in making engineering products.
Steel is a grey plastic material. It is heavier than aluminium but it is the hardest and the strongest of these three metals.
Copper is a red metal. It is harder and stronger than aluminium and more flexible than steel. But copper is the heaviest and the most expensive metal. The lightest and the most flexible of these materials is aluminium. It is a white hard metal.
Ответьте на вопрос
What kind of metal is aluminium?

Прочитайте текст
We use metals for a variety of engineering purposes. Some metals have ductile properties. If a metal is ductile, it can be pressed into a new shape. Copper is an example of this. It is a ductile metal because it can be stretched into another shape. Lead can be also pressed into a new shape.
Copper is a good conductor of electricity. We often use it for electrical conductors. And lead can be used for electrical cables because it resists corrosion.
Cast iron is unlike copper and lead. Its shape cannot be altered and it is not able to resist corrosion.
Ответьте на вопрос
What kind of conductor is copper?

Прочитайте текст
Many people have just returned from enjoyable holiday in the South West of England. But as well as being a major tourist attraction, this region also contains a healthy industry which provides a wide range of machining services.
The company set up in 1999 is a family-run business. It specializes in the machining of various precision parts.
Two years ago the company bought a new machining centre. ‘Much of our work involves machining different sizes of parts and producing large numbers of holes’, says the managing director. ‘This machine centre will help us become more efficient and reduce the level of skill required for certain key operations.’
Ответьте на вопрос
When was the company set up?

Прочитайте текст
The Egyptian pyramids are huge structures which are almost 4600 years old. The Pyramid of Cheops consists of 2300000 stones. Each of the stones weighs 2.5 tonnes.
According to the usual explanation large blocks of stone were cut in the mountains and then transported with the help of the most primitive equipment. So about 100 thousand people had to take part in the construction.
But the modern experiments show that the stones of pyramids were made synthetically. The Egyptians produced some special solution. Later they mixed it with one of the minerals. It took them several hours to transform this mixture into very hard rock. This rock was produced just on the construction sites and so there was no need of transporting heavy stones.
Ответьте на вопрос
How much does each of the stones weigh?

Прочитайте текст
Concrete is the name of artificial stone. The materials from which concrete is formed are sand, pieces of broken stone and cement mixed with water in suitable proportions. These materials are called ingredients of concrete. The sand and broken stone form the skeleton of concrete. Dry cement is an inert powder, but on the addition of water a chemical reaction takes place.
This causes the whole mix to set and harden forming a solid mix.
Water used in concrete mix is ordinary drinking water. It must be free from any impurities. The amount of water added influences the properties of concrete. Concrete products must be manufactured according with existing standards. Having chosen component materials builders must be well familiar with technology of concrete and use them in correct proportions.
Ответьте на вопрос
Which materials form the skeleton of concrete?