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【单选题】
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 comes from his gun before the sound reaches your ears. This great speed of light gives us 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 left the moon 1.3 seconds before it 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 case, the light from one of tonight's stars started on its journey to you before you were bola. Thus, if you want to be honest, you cant say' The stars are shining to night'? You have to say 'The stars look pretty. They were shining four years ago but their light has just reached Earth'. Sunlight seems to ______ than the light of the moon.
A.
have to travel a greater distance
B.
move less quickly
C.
travel much quickly
D.
be less powerfull
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【判断题】空间点A(1,-3,2)落在第五卦限?
A.
正确
B.
错误
【多选题】扣锅煅法注意事项( )
A.
煅烧过程中应随时用盐泥堵封
B.
药材不宜放得过多
C.
药材不宜放得过紧
D.
可根据米和纸的颜色来判断药材是否煅透
E.
药材煅透后应放冷再开锅
【判断题】发现自己眼中真正的生涯,意味着过自己真正要的生活。
A.
正确
B.
错误
【判断题】高校实验室废弃物必须要请有废弃物处置资质的单位进行清运处理。
A.
正确
B.
错误
【单选题】PS软件中,隐藏和显示参考线的快捷键是哪一个
A.
Ctrl+D
B.
Ctrl+H
【判断题】低压断路器具有短路保护和过载保护的作用
A.
正确
B.
错误
【单选题】血栓闭塞性脉管炎的病因及病理,下列哪项错误
A.
寒冷和潮湿的生活环境可以致病
B.
病变呈节段性分布
C.
病变累及动脉,不累及静脉
D.
病人多有吸烟史
E.
动脉周围有广泛纤维组织形成
【判断题】在利用等价无穷小量代换求极限时,对于加减乘除四则混合运算均可以进行等价替换。
A.
正确
B.
错误
【单选题】在 Android 源码目录结构中,哪一个目录中包含 JNI 的一些头文件?
A.
makefile
B.
ndk
C.
libnativehelper
D.
prebuilt
【简答题】快速隐藏和显示参考线的快捷键是 。
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