Test your understanding 3 (a) In a period where opening inventory was 5,000 units and closing inventory was 3,000 units, a company had a profit of $92,000 using absorption costing. If the fixed overhead absorption rate was $9 per unit, calculate the profit using marginal costing. (b) When opening inventory was 8,500 litres and closing inventory was 6,750 litres, a company had a profit of $62,100 using marginal costing. The fixed overhead absorption rate was $3 per litre. Calculate the profit using absorption costing