下列关于混合物、酸、碱、盐、氧化物分类完全正确的是（　　）

如图是康康同学探究物质性质时的连续操作步骤示意图，据此回答：

（1）操作中出现错误的步骤有（填步骤字母代号）____ ．

（2）写出步骤B中试管内发生反应的化学方程式　____ ．

（3）步骤B和步骤C中观察到的现象分别是____ ．

阅读理解

    I'm Li Ming．The holidays always make me happy．Last summer holiday,I went to Paris with my mother by plane．We went there to visit my uncle．He met us at the airport．

    My uncle took us to visit the Louvre Museum by underground．I saw a lot of famous things．I enjoyed many old pictures in it．The pictures were very creative(有创意的)．We also visited the Eiffel Tower．It is the famous symbol(标志)of Paris．One evening，my uncle took us to eat good food and go shopping．My mother bought many clothes-some for her,and some for my sister．

We stayed in Paris for about half a month.The trip gave me lots of fun.I will remember it.

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