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实验桌上有如图所示的实验装置(其中的透明玻璃为实验中的平面镜),还提供了一把刻度尺和相同大小的中国象棋棋子18个,9个为红色,9个为绿色 . 小军计划用这些器材探究“像的大小与物体到平面镜距离的关系”.

小军的主要实验步骤如下:


①将一个红棋子作为物体放在平面镜前面的白纸上,在平面镜后面改变一个绿棋子的位置,使得从不同角度观察,绿棋子与红棋子的像均完全重合,并记录实验数据 .

②不改变①中红棋子的位置,在其上叠放一个红棋子,在平面镜后面绿棋子上叠放一个绿棋子,使得从不同角度观察,两个绿棋子与两个红棋子的像均完全重合,并记录实验数据 .

③再改变四次物体的大小(改变叠放红棋子的个数),仿照步骤②,做四次实验 .

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    My dad was driving to the city center to shop and I was going along for the ride. At least that was what I had told him—   1  I had an important question to ask—that had been on my mind for a couple of weeks and this was the first time I had been able to 2with him alone.
  “Dad…”I started. And  3 .
  “Yes?” he said.
  “The kids say there is no Father Christmas. They say I'm   4  to believe in Father Christmas anymore…it's only for little kids. But I believe what you told me. Father Christmas is 5 . He is, isn’t he, Dad?”
  “The real life and spirit of this magical elf (精灵) lives forever in your heart, my heart, Mom's heart and in the hearts and minds of 6  people who believe in the joy that giving to others brings. The real   7  of Father Christmas becomes what you can give rather what you get. Once you understand this and it becomes  8  of you, Father Christmas becomes even more exciting and more magical because you come to   9  the magic comes from you when Father Christmas lives in your heart. Do you understand what I am   10  to tell you?”
    My heart was filled with pride and I’m sure my eyes were shining with   11 .” Of course, Dad. I want him to be in my heart, just like he's in yours. I love you, Daddy. You’re the best Father Christmas who has   12been in the whole world.”
    When it comes time in my life to   13  the reality of Father Christmas to my children, I hope that I will be as eloquent (有口才) and 14  as my dad was the day I learned that the spirit of Father Christmas doesn't wear a red  15 . And I hope they will accept me as I did that day. I'm sure they will.