Do characters have to be likable how can there be a connection to unlikable characters

No characters don't have to be likable. There could be a connection because it could be what you see in yourself. Reflection almost.

Explanation:

The reader can often relate to the unlikable character because the character resembles a part of the reader. Hope this helps!

the characters in string all have major secrets that they strive to avoid revealing throughout the play.

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.