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【简答题】
如图，抛物线y= 1 2 x 2 - 5 2 x与x轴交于O，A两点．半径为1的动圆（⊙P），圆心从O点出发沿抛物线向靠近点A的方向移动；半径为2的动圆（⊙Q），圆心从A点出发沿抛物线向靠近点O的方向移动．两圆同时出发，且移动速度相等，当运动到P，Q两点重合时同时停止运动．设点P的横坐标为t． （1）点Q的横坐标是______（用含t的代数式表示）； （2）若⊙P与⊙Q相离，则t的取值范围是______．
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举一反三
【简答题】选出下列单词的正确含义
【单选题】Why does the author believe that the surging sales of ebooks wont mean the death of the printed book?
A.
Because a minority will stick to their love of printed books.
B.
Because the majority of book lovers wont change their minds.
C.
Because people always hold nostalgic feelings towards printed books.
D.
Because people will return to the printed books as time goes by.
【单选题】复式记账的特点是（ ）。
A.
以“有借必有贷，借贷必相等”作为记账规则
B.
可以设置共同性质账户，即以账户的期末余额方向来判断账户的性质
C.
可进行试算平衡，以检查账户记录是否正确
D.
不要求对所有账户进行固定分类
【单选题】关于热射病的描述,哪项是错误的是：( )
A.
多起病缓慢
B.
临床特点为高热、无汗、昏迷
C.
直肠温度可超过41℃,甚至高达43℃
D.
可能有严重的神经系统症状
E.
救治的关键在于迅速降低体温
【单选题】Erasmus students can only take a course if they are also working.
A.
False. Students can work and can study at the same time.
B.
True. You need to have a job to become a student.
C.
False. You can simply study if you don’t want the professional experience.
D.
The text doesn’t actually raise this point.
【简答题】选出单词的正确含义
【单选题】Why does the author mention the high infant death rates in the last two paragraphs?
A.
To illustrate the inefficiency of the Government.
B.
As the data of Helen Christensen's research project.
C.
To illustrate the difficult pregnancy and motherhood.
D.
As the result of mothers' absent-mindedness and tiredness.
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