The air that people breathe is a mixture that contains primarily oxygen and nitrogen. The nitrogen generally makes up approximately 78%, while oxygen makes up 21%. Other gases, including carbon dioxide, hydrogen, helium, argon, and neon, make up the remainder. These gases dissolve and are carried in the blood.
Permissible work hours for 14- and 15-year-olds are: 3 hours on a school day; 18 hours in a school week; 8 hours on a non-school day; 40 hours in a non-school week; and; between 7 a.m. and 7 p.m., except from June 1 through Labor Day, when nighttime work hours are extended to 9 p.m. Child labor laws vary from state from state. Please consult your state department of labor for this information. DOL Web Pages on This Topic
Secondary jobs can be regular staff positions, temporary positions, or on-call positions. Hours worked in a regular (not temporary or on-call) secondary job are considered when determining benefits for employees that work a total of at least 30 hours a week for a 12 month period or 40 hours a week for a 9 month period.