1 to 2 hours a day is healthy.
if you mean how many hours you should sleep in a year it would be 3,650 hours of sleep for a regular year not a leap year
at least 3 hours
Hours of what?
eight hours
7 hours a week, for champions
8 hours
A nine year should be getting 9-12 hours of sleep.
3600 hours just kidding it is about 3500 seconds witch is 60 minutes witch is 1 hour
13 hours
Probably 8 hours
9 hours
A four year old should sleep 12 hours a day