Fоr questiоns 21–24, use yоur scrаtch pаper to workout the problems. Uploаd a file or image of your scratch paper in question 24. You may use your phone to take a picture of the paper and upload to the exam. Ensure your paper is clearly labeled with the question and answer. You will not given credit if the question or answer is unclear. Questions 21–24 are worth 20 points each.