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【简答题】
为了探究声音产生的原因，小明和一起做了几个实验：小明把手放在喉咙处，大声讲话，感觉喉头振动了；把发声的音叉放在水中，可以激起水花． (1)通过对上面的种种实验现象的分析，得出的结论：__ 。 (2)同学用手使劲敲桌子，发出很大的响声，但是他看到桌子几乎没有振动，为了使看到的实验现象更明显，你的改进方法是： _。 (3)小明、等同学在探究出上述问题之后，又提出这样一个问题：声音是怎样从发声物体传播到远处的？针对这一问题，他们经过认真地思考，提出了两种猜想： ①声音要传播出去，需要物质做媒介； ②声音要传播出去，不需要物质做媒介；究竟哪一种猜想是正确的呢？小明他们进行了如下的实验：如图，随着不断抽气，结果发现手机铃声越来越_（填“大”或“小”）由此现象可以推理：猜想___是正确的．
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离职率可以反映出企业对员工的吸引力和满意度
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对于企业而言，离职率为零最好
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企业应尽量降低有价值的、优秀的、核心的员工的离职率
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【单选题】The author argues that our bodies have stopped evolving because ______.
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life has been improved by technological advance
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the number of female babies has been declining
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the difference between wealth and poverty is disappearing
D.
our species has reached the highest stage of evolution
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【单选题】【A1 题型】 结核菌素皮内试验结果的观察应在注射后
A.
20分钟~1小时
B.
12小时
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24小时
D.
36小时
E.
48~72小时
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【简答题】The power and ambition of the giants of the digital economy is astonishing-Amazon has just announced the purchase of the upmarket grocery chain Whole Foods for $l3.5bn，but two years ago Facebook paid ...
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【单选题】The author argues that our bodies have stopped evolving because ______.
A.
life has been improved by technological advance
B.
the number of female babies has been declining
C.
our species has reached the highest stage of evolution
D.
the difference between wealth and poverty is disappearing
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【单选题】下列关于企业的离职率的表述错误的是( )。
A.
离职率可以反映出企业对员工的吸引力和员工的满意度
B.
对于企业而言,离职率为0时最好
C.
企业应尽量降低有价值的、优秀的、核心的员工的离职率
D.
将离职率保持在正常的、可接受的范围内,对企业利大于弊
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【简答题】Text 3 The power and ambition of the giants of thedigitaleconomy is astonishing -Amazonhas just announced the purchase of the upmarket grocery chain Whole Foods for $13.5bn, but two years agoFacebookp...
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【简答题】The power and ambition of the giants of the digital economy is astonishing-Amazon has just announced the purchase of the upmarket grocery chain .Whole Foods for $13.5bn, but two years ago Facebook pai...
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【单选题】结核菌素皮内试验结果的观察应在注射后 ( )
A.
20～30分钟
B.
1～2小时
C.
12～24小时
D.
48～72小时
E.
72小时以后
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【单选题】Don't get off until the bus _____. [     ]
A.
stopped
B.
will stop
C.
will have stopped
D.
stops
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相关题目：
【单选题】下列关于企业离职率的表述错误的是( )
A.
离职率可以反映出企业对员工的吸引力和满意度
B.
对于企业而言，离职率为零最好
C.
企业应尽量降低有价值的、优秀的、核心的员工的离职率
D.
将离职率保持在正常的、可接受的范围内，对企业利大于弊 prefix="o" ns="urn:schemas-microsoft-com:office:office"? ?xml:namespace>
查看完整题目与答案
【单选题】The author argues that our bodies have stopped evolving because ______.
A.
life has been improved by technological advance
B.
the number of female babies has been declining
C.
the difference between wealth and poverty is disappearing
D.
our species has reached the highest stage of evolution
查看完整题目与答案
【单选题】【A1 题型】 结核菌素皮内试验结果的观察应在注射后
A.
20分钟~1小时
B.
12小时
C.
24小时
D.
36小时
E.
48~72小时
查看完整题目与答案
【简答题】The power and ambition of the giants of the digital economy is astonishing-Amazon has just announced the purchase of the upmarket grocery chain Whole Foods for $l3.5bn，but two years ago Facebook paid ...
查看完整题目与答案
【单选题】The author argues that our bodies have stopped evolving because ______.
A.
life has been improved by technological advance
B.
the number of female babies has been declining
C.
our species has reached the highest stage of evolution
D.
the difference between wealth and poverty is disappearing
查看完整题目与答案
【单选题】下列关于企业的离职率的表述错误的是( )。
A.
离职率可以反映出企业对员工的吸引力和员工的满意度
B.
对于企业而言,离职率为0时最好
C.
企业应尽量降低有价值的、优秀的、核心的员工的离职率
D.
将离职率保持在正常的、可接受的范围内,对企业利大于弊
查看完整题目与答案
【简答题】Text 3 The power and ambition of the giants of thedigitaleconomy is astonishing -Amazonhas just announced the purchase of the upmarket grocery chain Whole Foods for $13.5bn, but two years agoFacebookp...
查看完整题目与答案
【简答题】The power and ambition of the giants of the digital economy is astonishing-Amazon has just announced the purchase of the upmarket grocery chain .Whole Foods for $13.5bn, but two years ago Facebook pai...
查看完整题目与答案
【单选题】结核菌素皮内试验结果的观察应在注射后 ( )
A.
20～30分钟
B.
1～2小时
C.
12～24小时
D.
48～72小时
E.
72小时以后
查看完整题目与答案
【单选题】Don't get off until the bus _____. [     ]
A.
stopped
B.
will stop
C.
will have stopped
D.
stops
查看完整题目与答案
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