题目

These days, we see a lot of shopping festivals. For Chinese shoppers, Singles’ Day is a big one, and it’s on November 11th.In the United States, Black Friday is the most well-known one.Black Friday always falls on the day after the Thanksgiving holiday. On this day, stores give special deals (特别折扣). Shoppers wake up very early. They wait in line (队伍) at stores before they open, but they might start to wait in line as early as 2 or 3a. m. Sometimes there are too many people. They are not able to get inside the store. Black Friday is not the only shopping festival in the US. An苏州的“碧螺春”享誉全国.“碧螺春”茶叶中的单宁酸具有抑制血压上升、清热解毒、抗癌等功效,其化学式为C76H52O46.下列说法错误的是( )A.单宁酸由碳、氢、氧三种元素组成B.一个单宁酸分子是由76个碳原子、52个氢原子和46个氧原子构成C.单宁酸中碳、氧元素的质量比为57:23D.单宁酸中氢元素的质量分数最小
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