Answer:
8,000 orders
Explanation:
At the given rates, 9 engineers should be able to process 12,000×9 = 108,000 orders. 8,000 more orders could have been processed.
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Comment on unused capacity
It is usually a good idea to try for 100% utilization of capacity only on the process constraining the rate at which money is being made. If there are constraints restricting the number of orders that can be filled, running Order Processing at full capacity can only result in unfilled orders and unhappy customers. It may have additional unwanted effects, too, such as increasing inventory of raw materials.