Which of the following is correct?
1- My teacher read my paper he said it was excellent.
2- My teacher read my paper, he said it was excellent

2 is correct

My teacher read my paper, he said it was excellent

Explanation:

The comma is needed.

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.