题干

1991年我国著名化学家张青莲教授,精确测定了铟(In)元素等相对原子质量新值.铟元素的核电荷数为49,相对原子质量为115.铟原子的核外电子数为(  )


A:115 

B:49  

C:66 

D:164

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B

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    It was one of the hottest days of the dry season.  If we didn't see any rain soon, we would lose everything.
One day when I was in the kitchen, I saw my six-year-old son, Billy, walking towards the forest. He was clearly trying to be as still as possible.   Several minutes after, he had gone into the forest, he ran out again, towards. the house.  This activity went on for an hour, walking carefully to the forest and running back to the house.  I really wanted to know what Billy was doing.
    Finally I followed him into the forest.  I found that he was holding a cup of water. He walked very carefully not to drop the water.
I saw a baby deer lying on the ground.  It lifted its head to drink the water in my son's cup.  After the deer drank up, Billy jumped up and ran back to the house to get more water.  When he saw me, he said, "I'm not wasting. " I found that his eyes were filled with tears.
    “I know. " I watched the most beautiful heart working so hard to save another life.Tears ran down my face.  As my tear drops began to hit the ground, other drops and more drops and more suddenly joined them   I looked up at the sky.   It was raining.
    Some people would say this was all just a huge coincidence  (巧合).   Those miracles(奇迹)  don't really exist (存在).  I would like to believe it was a miracle.   All I can say is that the rain that came that day saved our farm just like the actions of one little boy saved a life.