The Warehouse Company supplies spare parts for its two plants, Plant A and Plant B. Plant A and Plant B do not have any significant storage space. Hence you want carry minimum possible inventory at the plants A, B. The warehouse W stocks two types of spare parts,  part # A for the Plant  A and part #  B for  the Plant B. The  Warehouse Company uses a state of the art automated retrieval system (ARS) to retrieve parts from storage in the warehouse.

Part # A: The retrieval system takes one minute/unit to retrieve and send the part to the loading dock.

Part# B: The retrieval system takes one minute/unit to retrieve and send the part to the loading dock.

Whenever the retrieval system has to switch from part # A  to part # B, there is a "dead loss" of 30 minutes.

Whenever the retrieval system has to switch from part # B  to part # A, there is a "dead loss" of 30 minutes.

The demand for A at the Plant A is deterministic and is 15units l hr or 360units/day. The demand for B at the Plant B is deterministic and is 15 units l hr or 360units /day.

Assume, day = 24hrs. Thus, Plant A, Plant B, and the Warehouse Company are all open round the clock.

Plant A and Plant Band the Warehouse Company are all located in Chicago, and hence the transportation time from the loading dock of the Warehouse Company to the plants is negligible.

The goal is to use the ARS efficiently so as to keep the plants busy as much as possible. Design a scheme to use the ARS efficiently. Specifically,

How many units of part A will be retrieved and shipped before you switch to part B?

How many units of part B will be retrieved and shipped before you switch to part A?