Explanation:

**Setup Costs:**
Setup costs refer to the expenses incurred in preparing machines, equipment, or systems for a specific task or production run. These costs are associated with the activities required to bring the machines or systems to a working state for the production process. However, setup costs do not include certain expenses, which are explained below.

**a) Labour cost of setting up machines:**
The labor cost of setting up machines is a part of the setup costs. It includes the wages or salaries of the workers involved in the setup process. These workers are responsible for adjusting, configuring, and preparing the machines or equipment for the production run. Their efforts and time spent on setup are considered as setup costs.

**b) Ordering cost of raw material:**
The ordering cost of raw material is also a part of the setup costs. When preparing for a production run, it is necessary to ensure that an adequate amount of raw material is available. This may involve placing orders with suppliers, coordinating deliveries, and managing inventory. The expenses incurred in the ordering process, such as transportation costs, administrative costs, and any other associated fees, are considered setup costs.

**c) Maintenance cost of the machines:**
The maintenance cost of machines is not included in setup costs. Maintenance costs refer to the expenses associated with ensuring the proper functioning and upkeep of the machines or equipment. These costs may include routine inspections, repairs, lubrication, replacement of parts, and any other maintenance activities required to keep the machines in good working condition. While maintenance is necessary for the long-term efficiency and reliability of the machines, it is not directly related to the setup process.

**d) Cost of processing the workpiece:**
The cost of processing the workpiece is not included in setup costs. This cost refers to the expenses incurred during the actual production process, including the labor, energy, raw material consumption, and any other costs directly associated with transforming the raw material into the final product. Setup costs, on the other hand, are specifically related to the activities required to prepare the machines or systems for the production process and do not encompass the costs of processing the workpiece.

In conclusion, setup costs in the context of this question do not include the maintenance cost of the machines. Setup costs typically involve the labor cost of setting up machines and the ordering cost of raw material. The cost of processing the workpiece is separate from the setup costs as it is related to the actual production process.