Ros Nurseri has several manufacturing processes that involve the mixing of ingredients to create plant fertilizers. In two separate process operations, one such product is mixed. The information below pertains to the costs incurred in, and output from, Process 2 during the most recent period: Costs incurred: RM Transfers from Process 1 188,704 48,972 64,176 4,009 Raw materials costs Conversion costs Opening work in progress (Process 1 costs and Conversion costs) Production: Units Opening work in progress (100% complete, apart from Process 2 conversion costs which were 60% complete) 1,100 112,000 105,400 Transfers from Process 1 Completed output Closing work in progress (100% complete, apart from Process 2 conversion costs which were 75% complete) 1,700 Normal material waste (including product transferred from Process 1), which occurs in the end stages of Process 2 (after all materials have been added) is expected to be 3% of input. All conversion costs in Process 2 are allocated to units of good output. Materials that have been discarded have no resale value. Required: a) Using FIFO method, summarize total costs to account for and assign these costs to all related units. (17 marks) b) Explain equivalent units. Why are equivalent-unit calculations necessary in process costing? (3 marks)