Which step must happen before starting the timer?
a check the battery compartment.
b attach the cord.
c set the desired time.

citizens are given 25 years of life to prove their worth to society; if they fail to do great things

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.