a long slender part, such as the portion of a long bone between the wider ends or extremities, the shaft of a hair and the central shaft of a feather.
maximum number of hours for 16- and 17-year-old minors is 4 hours on a school day (6. hours with a special variance), 8 hours on a Friday or any non-school day and not more. than 6 days per week. The maximum number of hours of work for 16- and 17-year-old. minors is 20 or 28 (with the optional special variance).
1 Infants require about 14-15 hours a day. 2  Teenagers need about 8.5-9.5 hours on average. 3  Most adults need 7 to 9 hours a night for the best amount of sleep, although some people may need as few as 6 hours or as many as 10 hours of sleep each day.