FAA Regulation

They can maintain line of sight and without loss of control.  They briefed each other before the flight. They are in radio contact the entire time.

Visual observer.  Person manipulating the controls. Remote PIC.

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. 

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.

filed a IFR flight plan. received prior authorization from the controlling agency.  received prior permission from the commanding officer of the nearest military base.

Finish the mission by paying extra attention to the surrounding. Land as soon as practical and determine if the mission can be restarted without a Visual Observer.  Continue the mission without ...

No, this sUAS operation is not subject to Part 107. No, this sUAS operation requires a Section 333 exemption. Yes, this sUAS operation is subject to Part 107. 

100 mph 100 kts 87 mph