FAA Regulation

must not cause injury to a human being equivalent to 11 ft-lb of kinetic energy.  must have an approved type certificate issued under Part 21. must not cause injury to a ...

Yes, as long as the aircraft is equipped with an anti-collision light visible from 3SM. Yes, as long as the sUAS is equipped with Remote ID.  No, only transiting flights are ...

Continue the mission, airplanes are not allowed to fly lower than 500 feet AGL unless around an airport. Give way and stay clear from the crop duster.   Continue the mission, ...

No, Part 107 requires a Remote Pilot certificate. Yes, as a Student Pilot they can. Yes, under the direct supervision of a remote Pilot in Command. 

Visual observer. Person manipulating the controls. Remote Pilot in Command (Remote PIC). 

ensure that the human beings who are not participating in the operation are under a covered structure or inside a non-moving vehicle. ensure the sUAS is equipped with a parachute make sure the area is closed or restricted-access.

Without the possibility of direct human intervention from within or on the aircraft.  For hobby and recreational use when not certificated. During search and rescue operations other than public.