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Archimedes. Why in the first place was the ancient Greek scientist? First of all, because he is one of the greatest mathematicians of all times, close he came to the calculation of the number of "PI". Today all students and students of the daily study and enjoy the discoveries of the Greek. Also Archimedes was famous for the invention of many useful machines. Among these are the siege guns, and mirrors, поджигающие sails on the Roman ships by focusing sunlight. Archimedes made the first theorist of mechanics. For example, he presented the complete theory of the lever, applying it in practice. Also, scientists have developed a Archimedes screw (screw), with the help of which вычерпывается water and the present day. The primacy of the inventor of merit - all of it was opened more than two thousand years ago, when there were no computers, no technology available today, the inventors. Archimedes, perhaps, he studied in the libraries of Alexandria, but most of his knowledge was acquired independently.

1. Many folk-tunes were used in Tchaikovsky's compositions.
2. New methods of work in agriculture have been introduced by the agronomist.
3. A recently devised apparatus was showed lecturer's students.
4. Children must be looked after all of us.
5. The Russian delegation was given a hearty welcome by the population of France.
6. I was asked to help in the garden by the gardener .
7. The English text is being translating by the students.
8. Their work was finished earlier than usual.
9. A telegram has been sent.
10. The problem was being discussing by the students at 6 o’clock yesterday.
11. A new English dictionary must be bought.