Britain\'s Economy Britain lives by its industry and trade. With a population representing only 2 per cent of the world total, it is one of the largest trading nations in the world, providing about 10 per cent of world exports of manufactured goods. Jt is one of the\' biggest markets for food and raw materials: British agriculture, though highly efficient, produces just over half the country\'s food requirements and, apart from coal, some iron ore and oil and natural gas off the east coast, there are few mineral resources to supply the manufacturing industries. To pay for the food and other materials it needs, Britain relies on «invisible» exports — the provision of services such as banking, insurance, shipping. Aviation and tourism are also of great importance. The energy consumed in Britain comes from coal, pil, natural gas and nuclear power. The main centre of coal-mining is Wales. Most oil has to be imported. Over 90 per cent of the gas used in Britain is natural gas from the North Sea. Nuclear energy now produces about 10 per cent of Britain\'s electricity. Of Britain\'s total .population of about 56 million, some 25 million form the nation\'s workforce. A large proportion of this force is highly trained. About one million people are employed in banking, insurance and other financial and business services. The heart of all this activity is the City of London, although there are other important centres in several large cities, especially in ports such as Liverpool and Manchester, The City, about one square mile in the middle of .the capital; contains probably the greatest concentration of financial expertise in the world..The London Stock Exchange, with its vast experience and world wide network of communications, is one of the world\'s markets in securities. Another famous part of London, the West End, contains the leading international centre for the sale of works of art. The capital, with its wealth of historic buildings and museums, its theatres and concert halls, its fine restaurants, its shops and stores, is also the centre of Britain\'s large tourist trade.