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问题 填空题

一个梯形的上底是6厘米，下底是10厘米，高是0.4分米，它的面积是______平方厘米．

答案

0.4分米=4厘米

（6+10）×4÷2

=16×4÷2

=64÷2

=32（平方厘米）

答：它的面积是32平方厘米．

故答案为：32．

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Franklin D. Roosevelt was born in New York on January 30, 1882. He went to a famous high school in Massachusetts, and studied history in Harvard    小题1: three years, Roosevelt next    小题2: law(法律)and then worked in a famous New York City law firm. He entered  politics (政治) in 1910. For him, the future looked bright.    小题3:, in the summer of 1921,while having a holiday in Canada, he suddenly fell seriously ill and after that he became disabled. He was unable to walk any    小题4:. Not yet 40,he seemed finished in politics. But Roosevelt was not beaten down. Instead of    小题5: at home, he was still active in politics. He became president of the United States in 1933. He once said   小题6: his speech“The only thing we have to fear is fear    小题7:.”

Roosevelt was a man of unusual charm(魅力) , great optimism and strong will. He served  小题8:than any other president of the United States, and     小题9: the people of the United States through the hard times of the 1930s. He was in office from 1933 until his death in 1945, at the    小题10: 0f his fourth term (任期).
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单项选择题

传统的动物资源保护措施主要是划定保护区或建立保种基地。这些措施能很好地保护物种的多样性，但也存在一些缺点：保护区面积大，偷猎现象屡禁不止；建立良种基地保护地方品种投资大，时间长，容易出现近亲繁殖、物种衰退等现象。试管、克隆、冷冻保存等生物技术新成果的问世，为动物遗传资源的保护和利用开辟了新途径，建造“动物诺亚方舟”不再是天方夜谭。 这段文字主要介绍了( )。

A．保护动物物种多样性所取得的突破性进展

B．传统资源保护措施所遇到的困难和取得的进步

C．动物资源保护促成了生物技术新成果的诞生

D．生物技术的进步为动物资源保护开辟了新天地
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