Alberto Pharmacy produces Cure tonic using two herbs X and Y. Each litre of tonic requires 40 centiliters of X and 60 centilitres of Y. Weekly production varies from 350 ltrs to 450 ltrs, averaging 400 ltrs. Delivery period for both the herbs is 1 to 3 weeks. The economic order quantity for X is 600 Itrs and for Y is 100 ltrs. Calculate: (i) Reorder level of X, (ii) Maximum level of X, and (iii) Minimum level of Y