What things does the US government do to participate in trade?

What would happen to the tides if there was no moon and no sun in the sky?

The procedures for reporting potential unanticipated problems involving risk to subjects or others to the irb are: stated in the human subject protection regulations, but not in the drug or device regulationsincluded in the consent processdetermined by research staffdetermined by the institution in its written policies and procedures

How did dynasties end and how did new ones start?