I used to work for rotational shifts ,so time was no concern.
When i am working then never see my watch just because by my side working hours are not matters when your work is pending so first complete work then see how much you work
Mandatory 9 hours. Again it depends on your manager
9 Hours . Weekly 5 Days
Decent working hours. No complains there
9 hour 30 minutes per day
9 to 10 hours on an average