Jenny and Anne wanted to see who could throw a ball the hardest. They decided to each throw a ball against a wall as hard as they could and measure how far the ball rolled away from the wall. Out of the variables that you identified in this experiment, distinguish which ones you need to change, measure and control.

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.