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    A man was traveling abroad in a small red car. One day he left the car and went shopping. When he came back, its roof was badly damaged.

    Some boys told him that an elephant had damaged it. The man did not believe them, but they took him to a circus(马戏团) which was near there. The owner of the elephant said, “I am very sorry! My elephant has a big, round, red chair. He thought that your car was his chair, and he sat on it!"

    Then he gave the man a letter, in which he said that he was sorry and that he would pay for all the damage.

    When the man got back to his own country, the customs（海关） officers wouldn't believe his story. They said, “You sold your new car while you were abroad（国外） and bought this old one!"

    It was only when the man showed them the letter from the circus man that believed him.

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  单词拼写

某有机化合物A经李比希法测得其中含碳为70.59%，含氢为 5.88%，其余含有氧．现用下列方法测定该有机化合物的相对分子质量和分子结构．

方法一：用质谱法分析得知A的质谱图如下：

方法二：核磁共振仪测出A的核磁共振氢谱有4个峰，其面积之比为1：2：2：3，如图A．

方法三：利用红外光谱仪测得A分子的红外光谱，如图B．

一个等腰三角形的周长是30厘米，其中一条边长是8厘米，和它不相等的另一条边的长度可能是____厘米，也可能是____厘米。