题干

在练习使用打点计时器的过程中,下列说法正确的是(   )

A:两种打点计时器均使用4V﹣﹣6V低压交流电源

B:先接通电源,后释放纸带

C:拉动纸带前,应使拉动端停靠在靠近打点计时器的位置

D:测量各计数点间的距离时为方便操作可以直接分段测量

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答案(点此获取答案解析)

B,C

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    Every city, in fact, can be felt by its warmth-not in terms of its natural climate but its human touch.

    About twenty years ago, I arrived in Australia. Searching for a place in a map in the street, I was approached by an elderly man who asked “How are you? Are you lost? How can I help you?”, which really impressed and warmed me. Another time, as I was pushing my bike on the sidewalk one night, a young lady shouted to me: “Carry me please” and then jumped onto my bicycle. While we had a little chat, she got where she wanted and hopped off my bike with “Thanks, bye!” At that moment, I had a sense as much of pleasant surprise as of “being trusted”.

    Still in Australia, two of my friends decided to hitch(搭便车)their way to Sydney in order to save money. A young driver stopped, and luckily he was also going to Sydney, so he let them in and even allowed them to drive while he went to sleep on the back seat. About eight hours later, they arrived and he woke up. Saying thanks to each other, they went their separate ways.

    In my opinion, no matter how developed and advanced it is, if in general a place presents itself with a cold and indifferent(冷漠的)face to people, especially to strangers, even keeping them highly alert(警惕的)not to be cheated all the time, can perhaps hardly be classified as a land of civilization(文明). In a sense, the attitude towards strangers that the people have in the city mirrors its warmth.