把一只实心铁球放入一满杯水中，溢出水的质量为m₁，放入满杯酒精中溢出酒精的质量为m₂，(ρ_水＞ρ_酒精)(       )

代表网页文件的文件名后缀是下列选项中的哪一项。（   ）

我国东南沿海某市原为农产品和部分轻工业原料生产基地，1990年开始积极吸引外资，调整产业结构，建立起以化工、机械、纺织、电子、服装等为主的工业体系。下图是“该市1990～2010年产业结构变化图”。读下图，回答下列各题。

假定英语课上老师要求同桌之间交换修改作文，请你修改你同桌写的以下作文。文中共有10处语言错误，每句中最多有两处。每处错误仅涉及二个单词的增加、删除或修改。
增加：在缺词处加一个漏字符号(∧)，并在其下面写出该加的词。
删除：把多余的词用斜线（\）划掉。
修改：在错的词下划一横线，并在该词下面写出修改后的词。
注意：1）每处错误及其修改均仅限一词；
      2）只允许修改10处，多者（从第11处起）不计分。
    I will share with you true story that happened a couple of day ago. One of my classmates bought a bag of snacks from a food store. A few classmates were then inviting to enjoy the snacks. Unluckily, all of us got poisoned and had stomachaches with their faces pale. They were quickly sent to a nearby hospital. Doctors examined them but gave them some medicine. They were out of danger soon before taking the medicine. This accident makes us to realize the seriousness of the food safe problem. Therefore, I strong suggest that the whole society pays more attention to it.

I dance. I am a ____.