题干

如图是安装了漏电保护器的家庭电路.当漏电保护器检测到通过图中A、B两处的电流不相等(即发生漏电)时会迅速切断电路,从而起到保护作用:甲、乙两处分別装用电器和开关。对此电路,下列说法正确的是(  )

A:甲处应装用电器,乙处应装开关

B:电路中装有漏电保护器,更换灯泡不用断开电源

C:若图中C处不慎触电时,漏电保护器不会切断电路

D:若人体电阻为10kΩ,触电时通过人体的电流为22mA

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D

同类题1

阅读理解

    People often ask which is the most difficult language to learn, and it is not easy to answer because there are many factors to take into consideration. Firstly, in a first language the differences are unimportant as people learn their mother tongue naturally, so the question of how hard a language is to learn is only relevant when learning a second language.

    A native speaker of Spanish, for example, will find Portuguese much easier to learn than a native speaker of Chinese, for example, because Portuguese is very similar to Spanish, while Chinese is very different, so first language can affect learning a second language. The greater the differences between the second language and our first, the harder it will be for most people to learn.

    Many people answer that Chinese is the hardest language to learn, possibly influenced by the thought of learning the Chinese writing system, and the pronunciation of Chinese does appear to be very difficult for many foreign learners. However, for Japanese speakers, who already use Chinese characters in their own language, learning writing will be less difficult than for speakers of languages using the Roman alphabet.

    Different cultures and individuals will find different languages more difficult. In the case of Hungarian for British learners, it is not a question of the writing system, which uses a similar alphabet, but the grammatical complexity, though native speakers may find it easier, struggling with languages that the British find relatively hard.

    No language is easy to learn well, though languages which are related to our first language are easier. Learning a completely different writing system is a huge challenge, but that does not necessarily make a language more difficult than another. In the end, it is impossible to say that one language that is the most difficult language in the world.

同类题4

完形填空

    It has always been my dream to attend college. When I was younger, I would watch TV shows with college students having lots of 1.It looked like a great experience-going to parties,2with

    friends and letting the good times 3 When I entered high school, however, I started learning the real4 of college-to get a good education and a well-paid job. Therefore, with a passion for success in life, I expressed my 5about attending university to my parents. They were6I'd chosen the path, but were disappointed because they couldn't 7the cost. Upset and stressed, I started looking for 8to pay myself.

    My search for money began online. I went to every free scholarship search engine and spent up to five hours each day looking for scholarships I 9for. It was hard, but I knew it would10When I'd found almost all the scholarships I could apply for, I11them by deadline, which  gave me a way to prioritize my schedule. After12 everything, it was time to fill out the applications. Despite the amounts, ranging from$100 to $40,000, I took each scholarship13because together they would fund my goal. With this in my mind, the hardest part began: writing the essays. To 14my writing, I asked friends, relatives and teachers to15over my work. Now I've won16scholarships and can attend college for free.

    The scholarship search truly made me a17person. I learned the importance of setting a(n)18 and accomplishing it.19 I did have to read several rejection letters, those made me stronger. I'm thrilled I had the opportunity to learn more about my20to succeed no matter what difficulties got in my way.