A factory begins production at 500 units in the first month. The monthly output is planned to increase by 25 units each month until a maximum capacity of 800 units per month is reached, after which the output will remain constant at 800 units.
(i) Determine the month in which the production first attains the maximum capacity of 800 units.
(ii) Find the total number of units produced in the first 12 months.
(iii) If the manufacturing cost is ₹120 per unit for the first 12 months, calculate the total manufacturing cost incurred in this period.