如图是某同学设计的冶炼铁的实验装置，下列有关说法中正确的是（  ）

下列应用及相应的原理（用化学方程式表示）的是（　　）

阅读理解

    Blogit is the first online subscription（订阅） network connecting individual readers and writers．As Blogit grows, amazing things are happening．A friendly, active community has formed: readers are finding writers they enjoy; strangers are becoming friends; old classmates are running into one another; even romances are blossoming．And popular writers have already earned more than $1,000 on Blogit each month．

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    You never know whom you might meet on Blogit．Whether writers are looking for a quiet readership or are hungry for a spirited discussion, they will find it on Blogit. Many writers even have readers who have become new friends. Blogit member introduction appear on many of the top Internet search engines, which allows writers to publicize （宣传）their identity and helps increase their number of readers．

    Thanks to modern technology, writers get everything they need to begin．They can even make additional choices, to add pictures and select different styles, for example．There is nothing to install(安装), and no  special software is needed．As Blogit grows, we are upgrading（更新）our systems and adding new features(专题节目) requested by members．We do our best to help members, replying to most questions within one business day．

    I invite you to try Blogit today．Here' s my promise: if you find that you aren't being read on Blogit, simply cancel（取消） your subscription and you will not be charged again．It' s quick and easy to sign up．If you sign up now, you'll get all of Blogit's benefits for only $12．95 per month．You can start to be read and begin earning money directly!

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