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已知：Cu₂O+H₂SO₄=CuSO₄+Cu+H₂O。此变化过程中元素化合价发生改变的是（   ）

学校将组织同学们开展“打卡红色博物馆”的研学活动。阅读材料，回答问题。

材料：红色博物馆见证了中国从星星之火到伟大复兴的历史时刻；讲述了中国领导各族人民争取民族独立、国家富强的光辉历程；展示了开拓先驱们在苦难中求索、在风雨中前行所铸就的红色精神。

根据材料并结合所学知识，确立一个自己参观红色博物馆的研学主题，在图中选取三个与该主题相关的博物馆，写出它们的名称，分别列举与所选博物馆展出内容相关的史实，丰富你的研学内容。

如图， 是 的直径，点 是 延长线上的一点，点 在 上，且AC=CD, ．

I wonder how (start) the story.

Pronunciation and grammar is important in English learning, and so is v.

关于x的方程有正整数解，则整数a的值是（       ）

改正词语中的错别字。

聪名            娇傲            彩红           末来 

尔且            密蜂            沟买           坏绕 

求下列各式中的x：

阅读理解
Henry was from the United States and he had come to London for a holiday.
One day he was not feeling well. So he was to the clerk at the desk of his hotel and said, “I want to see a doctor. Can you give me the name of a good one?” The clerk looked in a book, and said, “Dr. Grey.”
“Is he expensive?”
“Well,” the clerk answered, “he always asks for his patients two pounds for their first visit to him, and 1.5 pounds for later visit.”
Henry decided (决定) to save 50 pence. When he went to see the doctor he said, “I’ve come again, doctor.”
For a few seconds the doctor looked at his face carefully without saying anything. Then he nodded and said, “Oh, yes.” He examined (检查) him and then said, “Everything's going as it should do. Just continue (继续)with the medicine (药) I gave you last time.”

He's just been appointed director of the publishing division.

求下图阴影部分的面积。（单位是cm）

词语模仿秀。

火辣辣：   

瑟瑟发抖： 

质量为m的带正电小球由空中A点无初速度自由下落，在t秒末加上竖直向上、范围足够大的匀强电场，再经过t秒小球又回到A点。不计空气阻力且小球从未落地，则(    )

WWW服务是目前因特网提供的文件传输服务的缩写。

读家乡“云南省示意图”，回答问题：

下列各句中加点成语的使用，不正确的一项是（   ）

找出100以内8和9的公倍数与最小公倍数。(按从小到大的顺序填写）

100以内8的倍数：。

100以内9的倍数：。

100以内8和9的倍数：。

8和9的最小公倍数是：。

等腰三角形的一个顶角是70度，它的一个底角是度，它又是一个角三角形。

已知一次函数y=2x+4的图象经过点（m ， 8），则m=．