题干

下列对某一主题知识归纳,正确的一组是

A.生活常识

B.物质鉴别

①胃酸过多的人应多饮用葡萄汁

②成年人缺钙易造成骨质疏松

①用CO2鉴别氢氧化钠和氢氧化钙溶液

②硝酸铵与氢氧化钠--一加水溶解

C.化学与生产

D. 化学实验

①钱态氮肥与草木灰混合使用可以明显提高肥效

②用电镀厂的废水直接灌溉农田,可提高水的利用率

①通入CO2能使不饱和石灰水变成饱和

②粗盐提纯实验中,每次使用玻璃棒,其作用都不一样

A:A

B:B

C:C

D:D

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答案(点此获取答案解析)

B

同类题1

阅读理解

    A few years ago, I took a sightseeing trip to Washington, DC. I saw many of our nation's treasures, and I also saw a lot of citizens on the street—unfortunate ones, like beggars and homeless folks.

    Standing outside the Ronald Reagan Center, I heard a voice ask. “Can you help me?” When I turned around, I saw an old blind woman with her hand extended. In a natural reflex (自然反射), I reached into my pocket, pulled out all of my loose change and placed it in her hand without even looking at her. I hated being disturbed by a beggar.

    But the blind woman smiled and said: “I don't want your money. I just need help finding the post office.” In an instant, I realized what I had done. I had acted with prejudice (偏见)---I had judged another person simply for what I thought she had to be.

    I hated what I saw in myself. This incident brought back my central belief. It reminded me that I believed in being humble (卑下的), even though I'd lost that belief for a moment.

    The thing I had forgotten about myself is that I am an immigrant (移民). I left Honduras and arrived in the US at the age of 15. I started my new life with two suitcases, my brother, my sister and a strong mother. Through the years, I have been a dish washer, roofer, mechanic, cashier and pizza delivery driver, among many other humble jobs. Eventually, I became a network engineer.

    In my own life, I have experienced many acts of prejudice. I remember a time at age 17---I was busboy (餐馆工), and I heard a father tell his little boy that if he did not do well in school, he would end up like me. I have also seen the same treatment of family and friends, so I know what it's like, and I should have known better.

    But now, living my American middle-class lifestyle, it is too easy to forget my past, to forget who I am and where I have been, and to lose sight of where I want to go. The blind woman cured me of my blindness. She reminded me of my belief in being humble, and to always keep my eyes and heart open.

    By the way, I helped that lady to the post office. And in writing this essay, I hope to thank her for the priceless lesson she gave me.