11 is fine t 30, its the ones at work who say they are in bed by 10 at the latest, one of them who is 32 says she is in bed by 9pm.
depends when they get up.
my schedule has been out of whack the last months but i normally go to bed 9:30 and get up at 5:30. 8 hours of sleep is highly recommended to avoid an early grave.