题干

小梁同学用实验测量某地大气压的值.她在长约1米,一端封闭的玻璃管里灌满水银,用手指将管口堵住,然后倒插在水银槽中,放开手指,管内水银面下降到一定高度时就不再下降,如图所示.

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阅读下列短文,从每题所给的四个选项(A、B、C和D)中选出最佳选项。

A

    Several months after I was badly hurt in a car accident, my father sent me to a blind school.

    That morning was the new beginning. I went to this school and I heard lots of children. My new teacher took me to the class where we were taught to write and type in Braille(盲文 ). I found it quite difficult.

    "Hi, sweetheart, how is school going?" asked my father.

    "Daddy, I can't do this. I try and try but I just don't get it. I don't know if I am ever going to learn to read Braille. It's too difficult," I cried.

    Daddy just held me in his arm and said, "Do you remember that we went to the temple which is on the top of a mountain? When we were climbing the mountain, my legs started aching. I sat down and said, 'I can't see the temple. You can't see it because it is covered with fog. Although you can't see it, I know it is here. I will make sure you will climb up to it.'"

    "That day you showed me that just you can't see something does not mean it is not there. So although climbing the mountain was difficult, I knew I would get to the top."

    I was clear what my dad wanted me to understand.

    I went back to school and started with new energy. Very soon I could read.

One of my classmates said, "You are lucky, you know, you have at least seen the world. I have just heard it. I have been told there are many colors in this world but I don't understand what color means."

    After listening to her for the first time in two years, I felt lucky. And on that day I learnt that although the light in my eyes is gone. I must see the world with the light in my heart.