Вопрос школьника по предмету Биология
отрицательное значение паукообразных
Ответ учителя по предмету Биология
1) Многие паукообразные являются вредителями сельскохозяйственных культур.
2) Переносят болезни, опасные для людей и домашнего скота.
3) Многие имеют опасные для человека и животных ядовитые железы.
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DIFFERENT KINDS OF LAND TRANSPORT
1.What was the reaction of the people after the invention of the steam engine?
In Washington the story is told of a director of the Patent Office who in the early thirties of the last century suggested that the Office be closed because “everything that could possibly be invented had been invented”. People experienced a similar feeling after the invention of the steam engine.
But there was a great need for a more efficient engine than the steam engine, for one without a huge boiler, an engine that could quickly be started and stopped. This problem was solved by the invention of the internal combustion engine.
2.Who introduced the first cheap motor car?
The first practical internal combustion engine was introduced in the form of a gas engine by the German engineer N. Otto in 1876.
Since then motor transport began to spread in Europe very rapidly. But the person who was the first to make it really popular was Henry Ford, an American manufacturer who introduced the first cheap motor car, the famous Ford Model “T”.
3.When did diesel-engined lorries become general?
The rapid development of the internal combustion engine led to its use in the farm tractors, thereby creating a revolution in agriculture. The use of motor vehicles for carrying heavy loads developed more slowly until the 1930s when diesel-engined lorries became general.
The motor cycle steadily increased in popularity as engines and tyres became more reliable and roads improved. Motor cycles were found well suited for competition races and sporting events and also recognized as the cheapest form of fast transport.
4.When were the trams introduced first?
Buses were started in Paris in 1820. In 1828 they were introduced in London by George Shillibeer, a coach builder who used the French name Omnibus which was obtained from the Latin word meaning “for all”. His omnibuses were driven by three horses and had seats for 22 passengers. Then in the 20th century reliable petrol engines became available, and by 1912 the new motor buses were fast replacing horse-driven buses.
Trams were introduced in the middle of the 19th century. The idea was that, as the rails were smoother than the roads, less effort was needed to pull a tram than a bus. The first trams were horse-drawn but the later trams were almost all driven by electricity. The electric, motor driving the tram was usually with electric current from overhead wires. Such wires are also used by trolleybuses, which run on rubber tyres and do not need rails.
Another form of transport used in London, Paris, Berlin, Moscow, St. Petersburg, Kiev and some other crowded cities is the underground railway.
London’s first underground railway of the “tube” type was opened in 1863, the Moscow underground in 1935.
5.What do the longest oil pipe-lines connect?
The pipe-lines, which were in use by the ancient Romans for carrying water supplies to their houses, are now mainly used to transport petroleum. The first pipe-line of this kind was laid in Pennsylvania, the United States, in 1865.
Some of the longest oil pipe-lines connect oil-fields in Iraq and near the Persian Gulf with ports on the Mediterranean coast. A famous Pipe-Line Under the Ocean (PLUTO) was laid across the English Channel In 1944.
6.What are the cableways used for?
A form of transport which is quite common in some mountainous parts of the world, especially in Switzerland, is the aerial cableway. Cableways are used at nearly all winter sport centres to pull or carry skiers to the top of the slopes. Cableways are used by many Alpine villages which lie high up the mountain-sides for bringing up their supplies from the valley below.
Что влияет на изменение природных зон Северной Америки не только с севера на юг,
но и с запада на восток?
А) тёплые течения;
Б) рельеф и воздушные массы;
В) солнечная радиация;
Г) океаны.