每年的3月22日是“世界水日”,水与人类生活和生产的关系十分密切.2012年“世界水日“的宣传主题是“水与链式安全”(Water and Food Security).请回答下列问题.
(1)①水能溶解很多种物质,但是却不能溶解油污.衣服沾有的油污,可加洗洁净洗去,是因为洗洁净具有
乳化
乳化
作用.
②二氧化碳溶于水中可制成汽水,喝了冰镇汽水以后,常常会打嗝,这种现象说明气体的溶解度与
温度
温度
有关.
(2)2010年上海世博会的园区内有许多饮水处,可取水直接饮用.所供的饮用水处理步骤如图所示:

步骤①中活性炭起
吸附
吸附
作用.
(3)降雨是自然界中水循环的一个环节.酸雨是由于空气中含有二氧化硫等酸性气体或这些气体在空气中反应后的生成物溶于雨水所形成.A、B、C三个地区雨水的pH如图所示,其中
B、C
B、C
地区的雨水是酸雨.
(4)电解水时,加入少量氢氧化钠或稀硫酸溶液的作用是
增强水的导电性
增强水的导电性

(5)每年世界各地都会有很多地区缺水面临旱灾.面对旱情,我们更要节约用水.写出一种生产、生活中常见的节水方法:
随手关闭水龙头
随手关闭水龙头
.人工降雨是缓解旱情的重要手段,干冰等物质可用于人工降雨.干冰用于人工降雨的原理是
利用干冰升华吸热,使空气中的气温下降,水蒸气液化形成降雨
利用干冰升华吸热,使空气中的气温下降,水蒸气液化形成降雨

In 1997, I found myself in a situation I never thought I'd be in: alone and begging for money in New York. My father had been separated from our family, and my mother had  recently died from complications related to AIDS. What I remember most about such nights is lying on the cold marble floor and using my backpack for a pillow.
Even though I had lost my family,  I made choices every single day to turn my life around. There was the haven for homeless teenagers called the Door, a non-profit organization that provided me with guidance, medical care and food, all of which kept me going while I completed my homework in train stations and under hallway lights. Perhaps the most surprising help though, I did not seek out﹔it found me.  The New York Times told my story. In the weeks that followed, dozens of strangers reached out to me from all across the United States. At my high school, I began receiving handwritten letters of encouragement. Strangers showed up bearing clothes, books, and even hugs. Since the article mentioned I was applying to Harvard, one woman knitted a blanket for me.  She attached this note to the box it was posted in: "It gets cold in those dorms. May you warm yourself knowing that people care about you".
With the help of these people, my life today bears no resemblance at all to my life then. I graduated not only from high school but also from Harvard University.
Before these people — some of them nameless— I just didn't realize how good people could be. But now I do, and I can say that the people who helped me have forever changed me. They are the reason behind my decision to join the board at the Door so that I can be part of a small team of people opening a high school for homeless teenagers .They are the reason I dedicate my life to opening pathways for others. And they are the reason I travel around the world helping people transform their own lives.
【小题1】According to the passage, the author______________.
A.tried to change her life
B.often slept m friends’ homes
C.felt lonely because of her illness
D.felt quite desperate for her father
【小题2】What can we learn about the Door?
A.It helps the homeless teenagers.
B.It is an organization seeking profits.
C.It provides entertainment for children.
D.It reports the stories about the homeless.
【小题3】The 3rd paragraph mainly tells about                       .
A.how the author applies to Harvard
B.how the author struggles for her ideal
C.how The New York Times helps the author
D.how people help the author in different ways
【小题4】Which of the following is the correct order to describe the author's life?
a. The newspaper reported her story.
b. She graduated from Harvard University.
c. She slept on the cold floor at night.
d. She joined the committee at the Door.           
e. Her mother died from the illness.
A.d→e→c→a→bB.e→c→d→a→b
C.e→c→a→b→dD.b→c→d→e→a
【小题5】What can we learn from the last paragraph?
A.Patience is a virtue.
B.Love can be passed on.
C.Time waits for no man.
D.Honesty leads to success.

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