Answer:
7.5 minutes
Explanation:
The problem says that each camera has 1 hour of digital space. Because you calculated that the total time of speeches will be 52.5 minutes, you can do as follows:
1 hour = 60 minutes
60 - 52.5 = 7.5
I hope this helped! You are going to do well in life! Never be afraid to ask your teacher or a fellow student for help!