共用题干单选题
共用题干单选题
辫状河（braided stream）
Why do airplanes take longer to fly west than east
It can take five hours to go west-east from New York(NY) to London but seven hours to travel east-west from London to NY. The reason for the difference is an atmospheric phenomenon known as the jet(喷射) stream. The jet stream is a very high altitude wind which always blows from the west to the east across the Atlantic. The planes moving at a constant air speed thus go faster in the west- east direction when they are moving with the wind than in the opposite direction.
2. What would happen if the gravity on Earth was suddenly turned off
Supposing we could magically turn off gravity. Would buildings and other structures (建筑物) float away What happened would depend on how strongly the things were attached to the Earth, The Earth is moving at quite a speed, moving at over a thousand miles per hours. If you turn something around your head on a string(细绳) , it goes around in a circle until you let go of the string. Then it flies off in a straight line. ’ Switching off’ gravity would be like letting go of the string. Things not attached to the Earth would fly off in a straight line. People in buildings would suddenly shoot up-wards at a great speed until they hit the ceiling. Most things outside would fly off into space.
A:It is the jet stream that affects how fast airplanes fly B:Planes go slower when they are moving with the wind C:It takes more time to fly from NY to London than from London to NY D:The jet stream always blows from the east to the west across the Atlantic
The (1) of the fluorescent tube (2) a major revolution in the development of better and cheaper lighting. First shown at the New York and San Francisco World (3) in 1939, this more efficient, more diffuse, longer-lived lamp has been (4) improved, so that slowly it (5) the supremacy of the incandescent household globe. The fluorescent tube (6) Australian homes, shops and factories today is seven or eight times (7) thetubes that brought shadow-free lighting to many of Britain’s wartime factories. Its (8) too, is much greater — from 2, 000 hours in 1940 to mc/re than 7, 500 hours today.
But (9) its (10) use for more than 30 years, the fluorescent tube remains a
(11) to many of its users. It is built (12) a completely different (13) from the incandescent light. In the incandescent bulb, a tungsten wire (14) than a human hair, is brought to white-hot temperature by passing an electric (15) through it. In the fluorescent tube a stream of electrons bombards a gas containingmercury, (16) invisible ultraviolet radiation. The ultraviolet rays hit the fluorescent coating that (17) the tube, (18) it to grow. A 40 watt ’fluorescent tube gives twice as much light as a 100 .watt tungsten globe, (19) about five times as long, and runs cool enough to (20) higher levels of light.
A:current B:stream C:flow D:flight
C
David was a young man who worked in an office in a big city. His hobby was fishing, but he didn’t often get a chance to practise it.
Then one summer he decided to have a holiday in a beautiful place in the mountains where here were a lot of streams. "I ought to be able to have some good fishing there," he said to himself.
The first morning after he arrived, he walked to the nearest stream with his fishing-rod. He aw an old man standing beside the water, so he asked him whether it was a private(私人的) stream. The old man answered it was not, so David then said to him, "Well, then it won’t be a crime(犯罪) if I catch some fish here, will it"
"Oh, no," answered the old man. "It won’t be a crime, but it will certainly be a miracle(奇迹)。"
A:Since no other persons are here, I wont disclose (揭发) it B:It will certainly be a miracle if I don't disclose it C:There isn't any fish in the stream D:I will surely report you to the owner of the stream
为读取的内容进行处理后再输出，需要使用下列哪种流 ( )
A:File stream Pipe stream Filter stream Random stream
Why do airplanes take longer to fly west than east
It can take five hours to go west-east from New York(NY) to London but seven hours to travel east-west from London to NY. The reason for the difference is an atmospheric phenomenon known as the jet(喷射) stream. The jet stream is a very high altitude wind which always blows from the west to the east across the Atlantic. The planes moving at a constant air speed thus go faster in the west- east direction when they are moving with the wind than in the opposite direction.
2. What would happen if the gravity on Earth was suddenly turned off
Supposing we could magically turn off gravity. Would buildings and other structures (建筑物) float away What happened would depend on how strongly the things were attached to the Earth, The Earth is moving at quite a speed, moving at over a thousand miles per hours. If you turn something around your head on a string(细绳) , it goes around in a circle until you let go of the string. Then it flies off in a straight line. ’ Switching off’ gravity would be like letting go of the string. Things not attached to the Earth would fly off in a straight line. People in buildings would suddenly shoot up-wards at a great speed until they hit the ceiling. Most things outside would fly off into space.
A:It is the jet stream that affects how fast airplanes fly B:Planes go slower when they are moving with the wind C:It takes more time to fly from NY to London than from London to NY D:The jet stream always blows from the east to the west across the Atlantic
Why do airplanes take longer to fly west than east
It can take five hours to go west-east from New York(NY) to London but seven hours to travel east-west from London to NY. The reason for the difference is an atmospheric phenomenon known as the jet(喷射) stream. The jet stream is a very high altitude wind which always blows from the west to the east across the Atlantic. The planes moving at a constant air speed thus go faster in the west- east direction when they are moving with the wind than in the opposite direction.
2. What would happen if the gravity on Earth was suddenly turned off
Supposing we could magically turn off gravity. Would buildings and other structures (建筑物) float away What happened would depend on how strongly the things were attached to the Earth, The Earth is moving at quite a speed, moving at over a thousand miles per hours. If you turn something around your head on a string(细绳) , it goes around in a circle until you let go of the string. Then it flies off in a straight line. ’ Switching off’ gravity would be like letting go of the string. Things not attached to the Earth would fly off in a straight line. People in buildings would suddenly shoot up-wards at a great speed until they hit the ceiling. Most things outside would fly off into space.
A:It is the jet stream that affects how fast airplanes fly B:Planes go slower when they are moving with the wind C:It takes more time to fly from NY to London than from London to NY D:The jet stream always blows from the east to the west across the Atlantic
您可能感兴趣的题目
