A skilled worker is allowed to take 9 hours to complete a job on daily wages and 6 hours on a scheme of payment by results. His daily rate is ₹75 per hour. The material cost is ₹400 and the overheads are recovered at 150 per cent of the total direct wages. Calculate the factory cost of the product under (i) piece-work plan, (ii) Halsey Plan and (iii) Rowan Plan, assuming work is completed in 6 hours.