Resource and duration estimation

The table below shows the relationship between preparation activities A through E for an event, the standard number of persons in charge for each activity, and the number of days required for each activity. On the basis of this table, preparation activities were started 35 days ago, but because of other activities only one staff member was assigned for the first 20 days. In order to perform the remaining preparation activities in time for the event, what is the minimum number of staff members that must be assigned per day? Here, each preparation activity has a manual, therefore, anyone can perform any activity and the activities can be performed in parallel. Editorial accessible table transcription: Preparation activity; Standard number of staff members; Required number of days. A: 2, 5. B: 2, 5. C: 3, 10. D: 2, 5. E: 5, 10.

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