Английский язык. Болсуновская Л.М - 63 стр.

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65
III. Переведите на русский язык следующие предложения.
1. The report will be followed by a discussion.
2. Ted doesn't like to be asked about his work.
3. At the end of May the students will be preparing for their
examinations.
Прочитайте текст и выполните задания после текста.
PRECIOUS METALS
Why are some metals so much more valuable than others? Gold, silver
and platinum have been highly valued for centuries because of their scarcity,
beauty and high qualities.
When Christopher Columbus discovered the America in 1492, Spanish
expeditions soon followed. Though they are much criticized for their cruelty,
greed and treachery, the military achievements of the 'Conquistadors' were
remarkable. First they conquered Mexico and took away its valuable
treasures. Seeking more land and wealth they invaded Peru, home of the
Incas. Here they murdered the king and stole his vast hoard of gold -
probably the greatest in the world. The natives were enslaved and set to work
to win more gold. Later the Spanish conquered Chile and Bolivia, both of
these countries being rich in precious metals, particularly silver.
To the metallurgists, the most exciting discovery made by the Spaniards
was the finding of platinum in the silver mines of Mexico. At that time the
new metal was regarded as more of a nuisance than of value. It could not be
melted by any known method, though it was possible to make a very realistic
imitation gold from it. Later it joined the group of precious metals and is now
used for jewellery and in industry. Its high melting point makes it suitable for
electrical contacts where the heat of sparks would melt other metals. In the
chemical industries its resistance to corrosion is of great value.
Gold is the most malleable of all the metals. It can be hammered into
sheets so thin that 250 of them would equal the thickness of a sheet of paper.
It is also the most ductile metal. One gram of gold can be drawn into a wire
1.8 miles in length.
Gold is the least chemically active of all metals and does not combine
with oxygen to form rust. This ability to resist corrosion makes it very
durable, i.e. it may last for centuries. Pure gold is too soft to be used in
jewelry so it is usually alloyed with other metals. The proportion of gold in
an alloy is measured in karats. Pure gold is 24 karats. A 14 karat gold ring is
an alloy of about 58% of gold and small percentages of copper and silver.
Silver is similar to gold in many ways. Like gold, it is very malleable and
ductile and so it is also used for jewelry. Silver differs from gold in that it is

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