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【简答题】
Light travels at a speed which is about a million times faster than the speed of sound. In one second, light travels about 300,000km, but sound travels only 344m. You can get some idea of this difference by watching the start of a race. If you stand some distance away from the starter, you can see smoke come from his gun before the sound reaches your ears. This great speed of light produces some strange facts. Sunlight takes about 8 minutes to reach us. If you look at the light of the moon tonight, remember that the light rays(光线)left the moon 1.3 seconds before they reached you. The nearest star is so far away that the light which you can see from it tonight started to travel towards you four years ago at a speed of nearly 2 million km per minute. In some cases the light from one of tonight’s stars started on its journey to you before you were born. Thus, if we want to be honest, we cannot say “ The stars are shining tonight.” We have to say, “ The stars look pretty. They were shining four years ago but their light has only just reached Earth.” 小题1: Light speed is ________ than sound speed. A.millions times faster B.a million times slower C.about millions of times faster D.about a million times faster 小题2:If you stand 200 meters away from a man who is firing a gun to start a race, you will find out that _____. A.you can hear the gun before you see the smoke. B.sound does not travel as fast as light. C.the sound of the gun will reach you before the man fires his gun. D.sound travels about a million times faster than light. 小题3:What does “ it” refer to? A.moon light B.light rays C.the nearest star D.the moon 小题4:The scientific way of saying “ The stars are shining tonight” should be________. A.the stars have been shining all the time. B.the stars seen tonight will be shining four years later. C.the stars were shining long ago but are seen tonight. D.the starlight seen today could be seen four years ago.
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举一反三
【单选题】某些产品在检验和测量时常有破坏性,宜采用
A.
普查
B.
典型调查
C.
抽样调查
D.
重点调查
【单选题】滑脂枪用于加注()。
A.
润滑油
B.
润滑脂
C.
机油
D.
齿轮油
【单选题】听力原文: You could say that Joseph Cornell became an artist because of his love of collecting. Cornell used to spend his free time exploring the street life of New York City in the 1920s. He soon started...
A.
He explored the night life of New York.
B.
He collected used boxes from the streets.
C.
He joined many art-related activities.
D.
He organized an artistic group.
【单选题】某工程项目期初投资1000万元,两年建成投产。投产后每年的净收益是150万元,请问该项目的投资回收期是多少( )
A.
8年
B.
8.67年
C.
8.7年
D.
9年
【单选题】某些产品在检验和测量时常有破坏性,宜采用( )
A.
普查
B.
抽样调查
C.
典型调查
D.
重点调查
【简答题】In 1826, a Frenchman named Niepce needed pictures for his business . But he was not a good artist . So he invented a very camera ( 照相机 ). He put it in a window of his house and took a picture o...
【判断题】外币兑换存在实际货币的转移,而外币折算则不存在实际货币的转移,只是改变报表的货币表述方式。
A.
正确
B.
错误
【单选题】Pablo Picasso is known for his abstract style. That means that his art looks out of this world. Picasso's father was also an artist. He started training him when Picasso was seven. When Picasso was 13...
A.
Space Relationship
B.
Time Sequence
C.
Examples and Illustrations
D.
Compare and Contrast
E.
Cause and Effect
F.
Addition (Enumeration) simple listing
【判断题】马斯洛的潜能论把成为创造性人才作为教育的终极目标。【 】
A.
正确
B.
错误
【单选题】对于价值较低的商品,一般采用( )计算其重量。
A.
以毛作净
B.
法定重量
C.
净重
D.
理论重量
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