Sinus cavities within the skull bones are strictly used only to lighten the mass of the skull. Agree or Disagree?

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Of good nutrition because it is essential to all forms of metabolism in the body

Employers are required to provide guardrail, safety net, or personal fall protection systems to protect workers from falling off unprotected sides/edges of residential roofs that are feet or more above a lower level.

What are used to respond to uncomfortable situations.