A bottling plant employs three different types of labour: unskilled manual workers, technicians and supervisors. It has estimated that the marginal product of the last manual worker is 200 units per week, the marginal product of the last technician is 275 units per week and the marginal product of the last supervisor is 300 units per week. The workers earn Rs.300, Rs. 400 and Rs.500 per week respectively.

i) Is the firm using the optimal combination of inputs? ii) If not, advise the firm on how to reallocate its resources.