Why have you decided they're not goc
- Propose two "rules" or guidelines for writing

Not only the two "rules" or guidelines for writing but an elaborate explanation of writing is explained below in detail.

Explanation:

answer: my favorite subject is choir

explanation: it is choir becuase you can sing and have fun singing at the same time with your friends.

the sentence that avoid faulty coordination is:

culture, which is well represented in philadelphia, plays a major role including theatre, music, and the visual arts.  

faulty coordination occurs when the writer gives equal importance two different ideas (clauses) which in fact are not equivalent. in order to correct a misplaced clause or idea, the writer can place less important or emphatic ideas in a relative clause as in the previous sentence.