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问题 选择题

我国是生物种类最丰富的国家之一。下列四种植物中，哪种植物是我国特有的珍稀植物？（   ）

A．银杏

B．雪松

C．银杉

D．侧柏

答案

答案：C

题目分析：银杉，是三百万年前第四纪冰川后残留下来至今的植物，中国特有的世界珍稀物种，和水杉、银杏一起被誉为植物界的“大熊猫”，国家一级保护植物，银杉是松科的常绿乔木，主干高大通直，挺拔秀丽，枝叶茂密，银杉雌雄同株，选C。

解答题

计算或化简：

（1）（-3）0+（+0.2）2013×（+5）2014

（2）2（x+4）（x-4）
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单项选择题

A physician who is too thorough in conducting a medical checkup is likely to subject the patient to the discomfort and expense of unnecessary tests. One who is not thorough enough is likely to miss some serious problem and therefore give the patient a false sense of security. It is difficult for physicians to judge exactly how thorough they should be. Therefore, it is generally unwise for patients to have medical checkups when they do not feel ill.
Which one of the following, if true, would most seriously weaken the argument in the passage

A．Some serious diseases in their early stages have symptoms that physicians can readily detect, although patients are not aware of any problem.

B．Under the pressure of reduced reimbursements, pbysicians have been reducing the average amount of time they spend on each medical checkup.

C．Patients not medically trained are unable to judge for themselves what degree of thoroughness is appropriate for physicians in conducting medical checkups.

D．Many people are financially unable to afford regular medical checkups.

E．(E) Some physicians sometimes exercise exactly the right degree of thoroughness in performing a medical checkup.
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