Which is a physical hazard in food?

Which of these is likely to be the best source of valid health information?

What is one technique to a person get proper sleep? eat a heavy meal before bed. exercise intensely before bed. practice relaxation breathing before bed. use electronics before bed.

Investigator a has biological specimens that are coded and linked to identifiers of the source individuals. investigator a provides the specimens to investigator b but does not provide the individual identifiers. investigator b agrees not to re-identify the source individuals. is investigator b's research using the biospecimens human subjects research according to the definition of human subjects research in the federal regulations?