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Light travels at a speed which is about a million times faster than the speed of  sound. 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 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 left the moon 1.3 seconds before they reached you. The nearest star is so far  away that the light that 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 had started on its journey to you before you were born. Thus, if we want to be honest, we can’t say, “The stars are shining tonight.” We   have to say instead, “The stars look pretty. They were shining four years ago, but    their light has only just reached the earth.” 小题1: Light speed is ______ sound speed A.as fast as B.a million times slower than C.about millions of times faster than D.about a million times faster than 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 sound before you see the smoke B.the sound does not travel as fast as light C.the sound will reach you before the man fires D.sound travels about a million times faster than light 小题3:Sunlight obviously (明显地) ______ than the light of the moon A.has to travel a greater distance B.moves less quickly C.travels much more quickly D.is less powerful(有力的) 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 shine four years later C.the stars were shining long ago but seen tonight D.the starlight seen today could be seen four years ago
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【简答题】证券投资技术分析的内容主要包括宏观经济分析、行业分析和区域分析、公司分析等。( )
【多选题】基本分析的内容主要包括( )。
A.
宏观经济分析
B.
行业和区域分析
C.
技术分析
D.
公司分析
【单选题】世界上第一台计算机诞生于哪个国家
A.
美国
B.
英国
C.
德国
D.
澳大利亚
【单选题】世界上第一台计算机诞生于哪个国家?
A.
英国
B.
美国
C.
加拿大
D.
日本
【单选题】世界上第一台计算机诞生于哪个国家
A.
英国
B.
美国
C.
法国
D.
德国
【单选题】PPT颜色拾取器从哪个版本开始加入这一功能?
A.
2007
B.
2010
C.
2013
D.
2016
【简答题】我刚刚丢了我的化学书。
【单选题】关于内梅罗综合指数,叙述错误的是()
A.
能综合评价几种污染物
B.
兼顾了极大分指数和平均分指数
C.
兼顾了权重和各分指数
D.
常在水环境综合评价中使用
【单选题】第一台计算机诞生于哪个国家?
A.
德国
B.
日本
C.
美国
D.
中国
【多选题】影响旅行社发展的技术环境分析的主要内容包括:
A.
技术水平和技术发展趋势
B.
技术对产业的影响
C.
技术的社会影响
D.
信息化影响
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