Common-size and trend percentages for a company's net sales, cost of goods sold, and expenses follow: Net sales Cont of goods sold Expenses Common-site Percentagon 2020 2019 2018 100.00 100.00 100.00 74.0 70.8 67.7 19.9 17.7 18.7 Trend Percentage 2020 2019 107.60 106.10 100.00 114.8 110.9 100.0 111.4 105.0 100.0 Required: a. Calculate the profit percentage for 2018, 2019 and 2020. (Round the final answers to 2 decimal places.) Profit Percentage nt 2018 2019 2020 b. Determine whether the company's profit increased, decreased, or remained unchanged during this three-year period. Pro