Calculate the ph when 40. 0 ml of 0. 150 m koh is mixed with 20. 0 ml of 0. 300 m hbro (ka = 2. 5 × 10⁻⁹).

Could we get the starts and then i can you!

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.