12 hours.
21
From 9am to 6:30pm is 9 hours and 30 minutes.
5 Hours
6 hours
Well, darling, if you can't count the hours between 9am and 6pm, I'm not sure what to tell you. But since you asked, that's a whopping 9 hours. Yes, 9 hours, sweetie. Time flies when you're having fun, or in this case, when you're stuck at work.
21 hours
There are zero hours between 9 am and 9 am.
11 hours
4 hours. 9am until noon is 3 hours and 1 more makes 4.
5.7
21