题干

在“探究凸透镜成像的规律”实验中,光具座上各元件位置如图所示,此时在光屏上恰好成一个清晰的像,则下列说法正确的是(    )

A:利用了这一原理制成了照相机

B:若将蜡烛远离凸透镜,则应将光屏靠近凸透镜才能得到清晰的像,且像逐渐变小

C:若保持凸透镜位置不变,将蜡烛和光屏的位置互换,会在光屏上成一个清晰倒立、放大的像

D:若保持凸透镜位置不变,将蜡烛放在刻度线45cm处,适当移动光屏也能得到一个清晰的像

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答案(点此获取答案解析)

B

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     One day, when I   2   a mobile phone store, I saw an advertisement on its door. It was hiring new workers!
“Sir, are you hiring people?” I went   3  the shop and asked. “Yes, but you should be the man who we need,” the manager answered. He looked at me for a few   4 from head to foot. “Do you have a high school diploma(文凭)?” 5 he, “Or do you have any work experience?”
    I felt so ashamed and  6 that I didn't know what to say, so I just turned around and left. I could not fall asleep that night, and I thought a lot about my  7  . “I must go to school or I can’t do anything without a good education,” I  8 to myself silently. I never went back to the store again 9 I finished my study and got a diploma.
10 looked the same when I returned to the store: the same people and the same design. However, compared with last time, I had more  11  . The manager told me they needed new    12  . So it was a great chance for me.
    I 13  my diploma to the manager. He looked at it and said, “Great, you are in.”
    Now I am still working in the same store. With this experience, I always  14 people to attend school. Education helps you have a bright future. Now I am not worried about my future because I'm still   15in my spare time.