《南京条约》规定：“英商进出口货物缴纳的税款，中国须同英国商定。”这一条款损害了中国的（   ）

工业上常以赤铁矿石（主要成分为Fe₂O₃）和焦炭为主要原料，在高温下炼铁．焦炭产生CO的反应是：

C+O₂CO₂；         C+CO₂2CO

（1）CO还原赤铁矿的化学方程式是　____ 

（2）下列说法正确的是____ 

a．为使赤铁矿石充分燃烧，需将其粉碎

b．足量的空气能提高炼铁反应速率

c．与生铁相比较，纯铁转化为“铁水”的温度低

（3）生铁的用途很多，某电镀厂用生铁将废水中的Cr₂O₇^2﹣转化为Cr³⁺，流程图1：

①气体A是____ 

②在上述酸性溶液中，生铁比纯铁产生Fe²⁺的速率快，原因是____ 

③将Cr³⁺转化为Cr（OH）₃的离子方程式是____ 　

（4）电解法将一定浓度的酸性废水中的Cr₂O₇^2﹣转化为Cr³⁺，其原理示意图2：

①阳极附近溶液中Cr₂O₇^2﹣转化为Cr³⁺的离子方程式是　____ 

②一段时间后，试管底部出现沉淀．解释生成沉淀的原因：____ ．

   I have a good friend at home. Her name is Mimi. She is white and yellow. She is very cute. I play with her when(当……的时候) I have time. She likes fish very much. When she is behind (在……之后) the sofa or in her box, you can’t see her. When I sit on the sofa, she sits with me. In the evening I do my homework at my desk, and she is on the desk. At that time I put her down(放下). Then she sits next to me. Is she a good friend of mine?