How is power shared at the national level in the United States?

What does mr. donald trump stand for in the matter of guns

Agroup of people who, because of their physical characteristics or cultural practices, are singled out and treated unequally.

According to ohrp, a problem is an “unanticipated problem” when it meets which of the following criteria: unexpected, related or possibly related to the research, suggests that the research does not put the subjects or others at greater riskunexpected, related or possible related to the research, suggests the research puts subjects or others at greater riskunexpected, unrelated to the research but still occurring with a subject, suggests the research puts others at greater riskexpected, related or possible related to the research, suggests the research puts others at greater risk