This business uses weighted average costing. The details of the process for the last period are as follows: Materials - $98,000 Labour - -$60,000 Production overheads $39,000 Units added to the process ----- -1,000 There were 200 units of opening WIP which are valued as follows: Materials -$22,000 Labour -- $6,960 Production overheads $3,000 There were 300 units of closing WIP fully complete as to materials but only 60% complete for labour and 50% complete for overheads. There were no process losses. Required: (A) Calculate the cost to be assigned to completed output for the period. (20 Marks) (B) Why is it necessary to calculate equivalent units?