4. BM Reid's books of account showed the following figures for the year ended 31 Decer Additional information: \180 of revenue was on credit 2 Inventory at 1 January 2019 was \\( \\$ 17500 \\) 3 Trade payables and trade receivables balances were unchanged since 1 January 2019. REQUIRED (a) Calculate the following ratios, correct to two decimal places, in each case stating the formula used. (i) Mark-up (ii) Inventory turnover (iii) Trade receivables turnover (iv) Operating expenses to revenue ratio (v) Current ratio (vi) Acid test/liquid ratio (vii) Non-current asset turnover. For the year ended 31 December 2018 the following ratios were: Inventory turnover 13 times; Trade receivables turnover 70 days REQUIRED (b) Use the above ratios to compare B M Reid's performance with the year ended 31 December. State possible reasons for the changes