In your chemistry class, suppose your final grade is based on a lab score, two major test scores, and a final exam score. There are 100 points available for each score. However, the lab score is worth 20% of your total grade, each major test is worth 25%, and the final exam is worth 30%. Compute the weighted average for the following scores: 91 on the lab, 83 on the first major test, 88 on the second major test, and 86 on the final exam.