This isn't really mathematics but I can give you an answer.
Assuming, it's in the dark (cuz in the light, why would you use flash), a person in the photograph can gain a red-eye (in the photo).
The only one I can think of is red eye.
Answer:
20 miles
Step-by-step explanation:
m<QRP=42degrees
m<Q=79degrees
m<P=59degrees
2800/560 = 5
It will take the plane 5 hours