Parker Ltd - continued: Required Task 3; Prepare the following planned values: a. Contribution and contribution / sales ratio (for each product and in total) and the gross profit (in total only - see note) 7 Marks b. Prepare a reconciliation to explain the difference between the total gross profits established using an absorption costing system (task 2 d.) and a marginal costing system (task 3 a.) 7 Marks Note to task 3 a. \& b.: The requirement of task 3 should be established using a marginal costing system where: - All direct costs are classified as variable - All indirect production overheads are classified as fixed The total task 3 mark above, includes marks allocated to short descriptive notes to workings (