No
No
No
No
When a sail boat overtakes a power boat the power boat is the stand on vessel.
The boat being overtaken is always stand-on, regardless of propulsion type. Rule 13.
No
power boat
power boat
Only when under sail alone and is crossing the path of a power boat.
only when under sail alone and when crossing the path of the power boat
The question should be "When is the sailboat the stand-on vessel...? The answer is if the sailboat has an engine and if it is in operation, the sailboat is treated as a power boat in determining stand-on status. The right-of-way would then follow the rules for power boats.
The overtaken vessel is ALWAYS the "stand-on" vessel, ALWAYS! Please refer to Rule 13 of the International Rules of the Road, AKA 72 COLREGS.