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问题 解答题

求以A（-1，2）、B（5，-6）为直径两端点的圆的一般方程．

答案

因为以A（-1，2）、B（5，-6）为直径两端点的圆的圆心坐标为（2，-2），

半径为

(2+1)2+(-2-2)2
=5，

所以（x-2）2+（y+2）2=25，即x2+y2-4x+4y-17=0

以A（-1，2）、B（5，-6）为直径两端点的圆的一般方程：x2+y2-4x+4y-17=0．

单项选择题

麻疹减毒活疫苗初次免疫年龄是（）。

A．生后1～2天

B．1个月以上

C．2个月以上

D．3个月以上

E．8个月以上
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多项选择题

请根据以下内容提示写一篇演讲稿

假设你正在参加全省中学生英语演讲比赛，请你针对有些父母经常翻看孩子日记或书包这一现象，写一篇演讲稿，陈述你的观点。

演讲稿的主要内容包括：

(1)认为同学们不必为此苦恼；

(2)希望能够体谅父母的苦衷；

(3)建议与父母进行交流和沟通。

注意：

①词数在120左右；

②可以适当增加细节，以使行文连贯；

③开头和结尾已为你写好，不计入总词数。

Good morning，ladies and gentlemen,

Some of us are having problems with our parents, as they often look into our schoolbags or read our diaries．（）

Thank you!

One possible version

Good morning, ladies and gentlemen,

Some of us are having problems with our parents, as they often look into our schoolbags or read our diaries. I fully understand why we are not comfortable about it, but there’s no need to feel too sad. Our parents are checking our bags or diaries to make sure we’re not getting into any trouble. They have probably heard some horrible stories about other kids and thought we might do the same. Or perhaps they just want to connect with us hut are doing it all wrong. My suggestion is: Tell them we want them to trust us as much as we’d like to trust them. If you don’t think you can talk to them, write them a letter and leave it lying around—they are bound to read it.

Thank you !
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