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sky123
2 năm trước
Bài 1.Tìm x biết a)(x+1)+(x+3)+(x+5)+...+(x+99)=9 b)(x-3)+(x-2)+(x-1)+...+10+11=11
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Read this text and choose the best answer. Just inside the walls of Florence stands a factory where silk is hand-woven on machines that date back to the fifteenth century. The factory, successful at the height of silk production in the eighteenth century, was almost unknown in the twentieth century until it was rescued about seven years ago by the Marchese Pucci, whose name has for so long been associated with beautiful and luxurious silks. Once again the factory is producing some of the most beautiful and expensive hand-woven silks in the world. Expensive they may be, but these silks are very strong, and the quality and colours are such that the cloth woven here will last at least one lifetime – probably several. The originator of all this beauty, the silkworm, is a sensitive little creature, living only on the freshly gathered and chopped leaves of the white mulberry. It is so nervous that loud noises, strong smells, or even the threat of thunder can kill it, so it is not entirely surprising that silkworm farming is so rarely practised in Britain today. In fact there have been several attempts, over the centuries, to start silkworm farming in England, but few of them have been successful. For example there was the attempt of James I who, though anxious to build up the silk industry, made a bad mistake and planted the black mulberry instead of the white. An easy error, and one that only the silkworms objected to. Although some silk is still grown in Italy, the Po valley, for example, is no longer covered by mulberry trees as it once was. The silk for the factory is sent raw from China – a journey almost as slow as it was in the second century. It is then dyed before being delivered to the Florentine building where it sits on the worn tiles waiting to be woven into bright butterfly – coloured cloth. The silk is protected from the light by protective cotton curtains. The patterns for the fabrics are made by using heavy cards which have holes in different designs, and allow selected lengths of silk through the holes, whilst rejecting others, thereby forming the designs, which vary greatly when the cloth is finished. 1. What is special about the silk factory described in the passage? a) It has always been owned by the Pucci family. b) It has been famous since the eighteen century. c) It was closed for 200 years. d) It uses very old machines. 2. The silk that is woven there is a) Expensive and long–lasting. b) Cheap and strong. c) Delicate and long–lasting. d) Cheap and colourful. 3. Why did James I’ s attempt to start silkworm farming fail? a) It was too cold in England. b) The silkworms were given the wrong food. c) The mulberry trees would not grow in England. d) The countryside was too noisy. 4. What happens to the silk when it reaches the factory? a) It is woven into a pattern. b) It is dyed. c) It is sorted into different lengths. d) It is mixed with cotton

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