8 hours.
7
6
Ten hours.
10 hours and 45 minutes.
12 hours 30 minutes.
10 hours and 15 minutes.
9 hours.
The time from 7:30 AM to 3:30 PM is 8 hours. This is calculated by counting the hours from 7:30 AM to 3:30 PM, which includes the intervals of 8 AM to 3 PM and the additional 30 minutes from 7:30 AM to 8 AM. Thus, the total duration is 8 hours.
9 hours
8 hours and 30 minutes.
Ten Hours
10.5 + 24k hours where k is any integer.