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问题 选择题

如图为6月22日与12月22日地球表面甲、乙两地的正午太阳高度。下列说法正确的是              

A．甲地地球自转线速度小于乙地

B．一年中甲地比乙地昼夜长短的变化幅度大

C．甲乙两地的正午太阳高度会在同一天达到最小值

D．从夏至到秋分乙地比甲地正午太阳高度变化幅度大

答案

答案：C

本题考查正午太阳高度的分析。甲地夏至日和冬至日的正午太阳高度相等，反映位于赤道上；乙地冬至日的正午太阳高度为90°，说明位于南回归线上，故夏至日时，两地的正午太阳高度都达一年中最小，C项正确。

单项选择题 A1/A2型题

半抗原的载体包括（）

A.脂类，蛋白质，多糖

B.类脂质，清蛋白，人工合成的多肽

C.清蛋白，球蛋白，人工合成的多肽聚合物

D.多糖，清蛋白，球蛋白

E.类脂质，球蛋白，大分子聚合物
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问答题

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