题干
已知
、
是不同的平面，
、
是不同的直线，则下列命题不正确的是 （ ）
、是不同的平面，、是不同的直线，则下列命题不正确的是 （ ）
A：若∥则
B：若∥,则∥
C：若![](http://tiku.21cnjy.com/tik </p>
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<a href="/question/4233020.html">上一题</a> <a href="/question/4233022.html">下一题</a> 0.0难度 选择题 更新时间:2018-10-17 08:10:27
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<h2 class="title daan" data="4233021">答案(点此获取答案解析）</h2>
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B
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若X﹣B（n，p），且E（X）=6，D（X）=3，则P=（ ）
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诗句、作者及作者所生活的朝代搭配有错误的一项是（ ）
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在48mL0.1mol/LHCl溶液中加入12mL0.4mol/LKOH溶液时所得的溶液呈
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<p>2016 年我国国内生产总值增长目标设定为6．5％～7％，保持经济运行在合理区间。为实现上述目标，我国应该（ ）</p><p>①实施强经济刺激政策→财政减收增支→投资需求扩大→经济增长</p><p>②结构性减税→减轻企业负担→提高企业盈利水平和发展能力→经济增长</p><p>③调结构→淘汰过剩和落后产能→促进企业升级转型→经济增长</p><p>④实施积极的货币政策→企业融资成本降低→创新能力增强→经济增长</p>
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阅读理解<br/><img data-cke-saved-src="/Upload/site3/6/6/66dca7f4a42d6dd15ef95072f774440f.png" src="/Upload/site3/6/6/66dca7f4a42d6dd15ef95072f774440f.png" v:shapes="图片_x0020_2" height="119" width="87"><br/> What is the first thing you want to do when you see someone yawn? You want to yawn, too! Yawning is <u>contagious</u>.<br/> Scientists have found that all people yawn. Babies start to yawn even before they are born. The earliest yawn takes place when a baby is still inside its mother. When young children are about one year old, they start to yawn when they see others yawning. That)
It's no secret that yawning is contagious, but why do we yawn? Well, scientists are not really sure.
Some think we yawn because we feel bored. Others believe yawning has something to do with breathing. When there is too much carbon dioxide(CO2) in our bodies, our bodies will tell the brains to breathe deeply. That causes a big yawn.
In 2007, scientists said people yawned to cool down their brains. These scientists found people yawned more often if they were warmer than others.
Scientists are still trying to find out why yawning happens and why it is so contagious. But they are only sure that when one person yawns, immediately everyone else nearby wants to yawn, too.