题目

I decided to go back to school in the fall of 2010 for not being happy with my current job and financial status. I got my Associate (大专毕业证书) in May 2002 in commercial art. After graduation, I had trouble getting a job in that field. For years, I was going from one job to another, and I was not satisfied with unstableness (不稳定).I decided to go back to school to study either international business or psychology (心理学). I weighed the pros and cons of both professions and psychology won. I like helping my friends and family. When they are faced with hard situations in 16、请你写出下列物质的化学式（1）氧化铜CuO；（2）氧化镁MgO；（3）四氧化三铁Fe3O4；（4）过氧化氢H2O2；（5）高锰酸钾KMnO4；（6）五氧化二磷P2O5．