hi, i m new to AP chem, this is my second week in that class , and our teacher assigned this AP Exam question from 1970 to us.

A 2.000 gram sample containing graphite (carbon) and an inert substance was burned in oxygen and produced a mixture of carbon dioxide and carbon monoxide in the mole ratio 2.00 : 1.00. The volume of oxygen used was 747.0 milliliters at 1,092 K and 12.00 atmospheres pressure. Calculate the percentage by weight of graphite in the original mixture.

Can anyone tell my what it's asking, how to solve it, and the answer?

Thanks!