A foundry is engaged in the production of castings. The process involved are (a) foundry work (b) turning (c) drilling (d) inspection and (e) packing. the foundry produces 1 kg (net) castings at a cost of Rs.3.50 per casting and thereafter the costs are as under: Cost of turning Rs.1.75, Cost of drilling Rs.1.25, Cost of inspection (at all stages) and packing per unit Rs.0.50. Inspection rejects 2 castings per 100 on completion of turning and 3 castings on completion of drilling process. The rejected castings after turning are sold for Rs.1.80 per unit and those after drilling at Rs.1.75 per unit. Credit sale of scrap is Rs.2.50 per 100 castings put through. Assuming that 10000 castings are put through each month, prepare a process cost sheet indicating the final output and net cost per unit.