Final answer:
The assumption that is not part of the basic EOQ model is delivery is gradual.
Step-by-step explanation:
The basic Economic Order Quantity (EOQ) model is used to determine the optimal order quantity for inventory management. The assumptions of the basic EOQ model include:
Therefore, the assumption that is not part of the basic EOQ model is c) delivery is gradual. In the EOQ model, it is assumed that delivery is instantaneous.