propane gas reacts with oxygen gas to give carbon dioxide gas and water vapor (gas). if you mix propane and oxygen in the correct stoichiometric ratio, and if the total pressure of the mixture is 300 mm hg, what are the partial pressures of

It depends on the subject for me. some exams are easier than others so i usually go through it and answer questions i know based on my general knowledge, then double check after. going through the lesson can a lot  because the exams can be  very lesson-specific, but sometimes they are ridiculously long so a lot of people don't take the time. i did find that, when i went through the lessons, i was making 100's on my exams vs strictly using + the internet and  i make 90's.