It was found that 65% of individuals use herbicides for commercial purposes, 27% of individuals use herbicides for agriculture purposes, and 8% of individuals use herbicides for home and garden purposes. Of 5 people who said that they used herbicides, find the probability that 3 used them for commercial purpose, 1 used them for agriculture purposes, and 1 used them for home or garden purposes. (Hint: use Multinomial distribution)

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. 

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