its recommended 7 to 8 hours
280 hrs
yes there are many phases in sleeping
20
at least 8-10 hours sleep
a 150 pound person sleeping for 8 hours burns 489 calories.
The duration of The Sleeping Child is 1.58 hours.
The duration of The Sleeping Tiger is 1.48 hours.
The duration of The Sleeping City is 1.42 hours.
The duration of Sleeping Bride is 1.67 hours.
The duration of Sleeping Luck is 1.75 hours.
The duration of The Sleeping Cardinal is 1.4 hours.
The duration of The Sleeping Dictionary is 1.82 hours.