From 8:15am to 6pm is 9 hours and 45 minutes.
8
1800 - 1000 = 8 hours
8 and 2/3 hours 8 hours, 40 minutes
10 hours
24 hours
48 hours.
8:15am to 6pm is 9.75 hours (9hours 45 minutes)
15
It's 120 hours between 6pm Thursday until the following Tuesday at 6pm
72 hrs
13 hours