You may see the words in senctence like:文中附相关图片 Which mean: Enlosed related pictures in the article. "文中"means in the article, AND "附" means enclosed. The two Chinese character can not be understand together. They belong to different structure. There is no such a word. They are just be placed together but can only have meaning with other words

Not sure of the context. I just saw it on what looked like a flag. (One someone's facebook)

BTW, 「什麼」 is also written as 「甚麼」 in Taiwan.

It doesn't mean anything, out of context, we can't tell the meaning of these 2 characters without context, I guess something must stands before or after it...

附中 would make sense i think.