Explanation
When you create a blanket purchase order for several minor repairs that may occur during the year, you must enter the following data:
An account assignment category, which determines how the costs for the repairs are allocated to an account assignment object such as cost center or order.
An overall limit value, which specifies the maximum amount that can be invoiced for all items within the validity period of the blanket purchase order. References: SAP S/4HANA Sourcing and Procurement
| SAP Learning, Course S4520, Unit 2, Lesson 1.

Explanation
Centrally agreed contracts are contracts that are created by a central purchasing organization and can be used by multiple purchasing organizations within a company. Some of the characteristics of centrally agreed contracts are:
You can use centrally agreed contracts in a procurement hub scenario, which means that you can leverage the central purchasing organization's negotiation power and expertise to procure materials or services for other purchasing organizations.
You cannot specify plants in centrally agreed contracts, which means that the contracts are not plant-specific and can be used by any plant that belongs to the purchasing organizations that are assigned to the central purchasing organization. References: [SAP Help Portal], [SAP Help Portal]

Explanation
To determine the safety stock during automatic reorder point planning, the system requires the following data:
Service level, which is the probability of avoiding a stockout situation during the replenishment lead time.
Mean absolute deviation, which is a measure of the forecast accuracy based on the historical consumption data.
Replenishment lead time, which is the time required to procure or produce a material. References: SAP S/4HANA Sourcing and Procurement | SAP Learning, Course S4525, Unit 1, Lesson 1.

Explanation
The Delivery Completed indicator in a purchase order item signals that no more goods receipts are expected for this item. Some consequences of setting this indicator are:
You can still post goods receipts of remaining quantities if you have not received the full ordered quantity yet. However, you cannot post goods receipts that exceed the ordered quantity.
The purchase order item is skipped when delivery reminders are generated by the system. Delivery reminders are messages that are sent to vendors to remind them of overdue deliveries orupcoming delivery dates. References: SAP S/4HANA Sourcing and Procurement | SAP Learning, Course S4520, Unit 2, Lesson 1.

Explanation
When you enter a supplier invoice for a purchase order that has already been delivered, you can use the following documents as a reference:
Delivery note, which is a document issued by the vendor that confirms the delivery of goods and contains information such as delivery date, quantity, and weight.
Goods receipt, which is a document posted by you that records the receipt of goods from a vendor and updates the stock and inventory data. References: SAP S/4HANA Sourcing and Procurement | SAP Learning, Course S4515, Unit 1, Lesson 1.