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勒洛四面体是一个非常神奇的“四面体”，它能在两个平行平面间自由转动，并且始终保持与两平面都接触，因此它能像球一样来回滚动. 勒洛四面体是以正四面体的四个顶点为球心，以正四面体的棱长为半径的四个球的公共部分，如图所示，若正四面体ABCD的棱长为a.
① 能够容纳勒洛四面体的正方体的棱长的最小值为a
   
② 勒洛四面体能够容纳的最大球的半径为
③ 勒洛四面体中过三点的截面面积为
④ 勒洛四面体的体积
上述命题中正确的是__________

设整数集合,其中 ，且对于任意，若，则
（1）请写出一个满足条件的集合;
（2）证明:任意;
（3）若,求满足条件的集合的个数.

已知数列满足，且，若使不等式成立的有且只有三项，则的取值范围为（       ）

A．	B．
C．	D．

已知函数.
(1)若对任意的恒成立，求t的取值范围；
(2)设且，证明：.

已知和为椭圆：的左顶点和右顶点，点是椭圆上不与和重合的动点，若点与点位于直线异侧，且满足，，则（       ）

A．点在椭圆的外部	B．点的轨迹为椭圆
C．	D．面积的最大值为

阅读下面短文，根据所给情节进行续写，使之构成一个完整的故事。

It was 8 o'clock on Sunday. Amy still stayed in bed, listening to the radio. Her mother, Hannah, asked her to switch off the radio and finish her homework, but she didn't listen. Her mother went out of the room with anger.

Next morning, Amy went to school cursing（咒骂）everyone possible for having to go to school. Even in school, Amy had a reputation（名声）of sorts for all the wrong reasons. She slept in class and did not finish her work. In playtime, Amy had to go out and play, but she tried to find an excuse saying that she was tired when someone caught her walking away.

She came home with leftovers in her lunchbox or other complaint almost every day, and that day was also no different.

"Who can help me to change my daughter?" Hannah wondered.

Hannah never believed in raising her voice or raising her arm on Amy or on anyone for that matter. She believed and wished that her love and patience would one day change Amy.

One day a new family moved into Amy's apartment. They were very friendly people. They wanted to acquaint（使…熟悉）themselves with all the neighbors, so their little girl , Mary, was sent all around the neighborhood to find friends. Soon, Mary carne to Amy's home.

It didn't take much time for Mary to understand Amy. However, she was not put off by Amy's behavior. She knew that she needed to help Amy to change. She told Amy an idea that her teacher had once told the class in her previous school. "Blow a balloon whenever you're angry or upset about something or someone.

At first Amy did not listen to Mary, but Hannah tried her best to tell her that it was fun and brought her a pack of balloons.

That day, Amy wanted to play a guessing game with her mother, but Hannah wanted to finish her chores（杂活）in the kitchen first. Amy got angry.

注意
1.续写词数应为150词左右；
2.请按照如下格式在答题卡的相应位置作答。
Paragraph 1:

She remembered what Mary told her and thought she would give it a try.

____________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________
Paragraph 2:

Amy is a changed person now.

____________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

如图所示，A板发出的电子由静止开始经加速后，水平射入水平位置的两平行金属板间，金属板间所加的电压为U，电子最终打在光屏P上，关于电子的运动，下列说法中正确的是（　　）

A．滑动触头向左移动时，电子打在荧光屏上的速度不变

B．滑动触头向右移动时，电子打在荧光屏上的位置下降

C．电压U增大时，电子打在荧光屏上的速度大小不变

D．电压U增大时，电子从发出到打在荧光屏上的时间变大

如图所示，在一个倾角为的足够长的固定斜面上，由静止释放一个长度为L＝5m的木板，木板与斜面之间的动摩擦因数。当长木板沿斜面向下运动的速度达到时，在木板的下端轻轻放上一个质量与木板相同的小煤块，小煤块与木板之间的动摩擦因数。设最大静摩擦力等于滑动摩擦力，取，，，结果可用根号表示。求：
（1）刚放上小煤块时，长木板的加速度的大小和煤块的加速度的大小；
（2）从放上煤块到与板共速经历时间；
（3）最终小煤块从木板哪一端离开；二者共速到二者分离又经历时间。
   

美国历史学家J．布卢姆说：“……全世界都说过，像美国规模这么大的国家，要建立共和制度是不可能的。……但是这里居然兴起了一个新型的共和国，一个虽然疆域和人口扩大十倍，但依旧对人民负责的政府，一个其人民不是作为相互对垒的公民，而是作为一个国家的平等公民联合起来的联邦。”美国共和制度得以确立的关键性措施是美国推行

A．三权分立的政治原则

B．中央集权的联邦制原则

C．人民民主的选举原则

D．保障人民基本权利原则

南朝时期，被视为弥勒菩萨化身的傅大士（傅翕），见梁武帝时身着道冠、儒履、佛袈裟。相传，东晋高僧慧远送别来访的儒士陶渊明、道士陆修静，不觉破例过了所居庐山东林寺外的虎溪桥，相与大笑，留下“虎溪三笑”的佳话。材料可用于说明当时（     ）

A．儒家的正统地位已经丧失	B．儒、佛、道的差别已消失
C．统治者奉行三教并行政策	D．儒、佛、道三教交融发展