已知关于的方程有实根，复数，则复数在复平面内的对应点到原点的距离为

A．2                B．4             C．            D． 8

如图所示，竖直平面内的3/4圆弧形光滑轨道半径为R，A端与圆心O等高，AD为与水平方向成45°角的斜面，B端在O的正上方，一个可看成质点的小球在A点正上方由静止开始释放，自由下落至A点后进入圆形轨道并恰能到达B点。求：

（1）到达B点的速度大小；

（2）释放点距A点的竖直高度；

（3）小球落到斜面上C点时的速度大小。

如图所示，竖直平面内的3/4圆弧形光滑轨道半径为R，A端与圆心O等高，AD为与水平方向成45°角的斜面，B端在O的正上方，一个可看成质点的小球在A点正上方由静止开始释放，自由下落至A点后进入圆形轨道并恰能到达B点。求：

（1）到达B点的速度大小；

（2）释放点距A点的竖直高度；

（3）小球落到斜面上C点时的速度大小。

（一）根据下列句子所给汉语意思写出空缺处单词，或根据所给词写出正确形式。
【小题1】If you want to go to the party with me, you should        (表现好) well.   
【小题2】There were several new          (arrive) at the hotel last night.       
【小题3】It's illegal to read people's private letters without        (允许). 
【小题4】You are only         (稍微) underweight for your height.
【小题5】The Prime Minister has formed a new       (内阁).
（二）根据下列句子所给汉语意思完成句子。
【小题6】It’s going to rain. Xiao Feng, will you please help me                (收衣服) on the line?
【小题7】                 （已经确认）that the 31^st Olympic Games will be held in Brazil.
【小题8】Is it __________(在步行距离内)or do I need to take a bus？
【小题9】Firstly, we should                  life. (养成对…的好态度)
【小题10】In recent years, many of my friends have come to big cities to               .(追求幸福与成功)

阅读下面短文，根据以下提示：1）汉语提示，2）首字母提示，3）语境提示，在每个空格内填入一个适当的英语单词，并将该词完整地写在右边相对应的横线上。所填单词要求意义准确，拼写正确。

     People often don’t do what they really want to for fear

of failure. You don’t apply for a job ______ case you don’t

get it. You don’t perform at the school concert b       others

might laugh at you. A lack of confidence can l       to a lot

of suffering. The key to o       this problem is to believe in

yourself. This might be        （容易）said than done, but there

are many w       to help you do this. Talk about your problem

with a friend or look        advice on the Internet. Imagine

yourself being        (成功) and practise breathing techniques

to keep you calm when you get nervous. And the        important

thing is: believe you can do it. When you’ve ______（学会）to do

that, you are well on your way.