Two people were notified in the second minute (others can be notified if they already know).
In the third minute, four people were notified.
In the 4th minute, 8 people were notified again.
At the 5th minute, notify 16 people again.
At the 6th minute, notify the remaining 19 people.
Six minutes is enough.
Mathematics examination questions for the final exam of senior one 1. Multiple choice questions: (5 points for each small quest