First off it depends on your starting point. Then you have to take into account the differences in time zones (forward and backward), speed of the aircraft, delays because of weather, lost luggage, airport security. In all reality, with no known starting point you can conceivably fly anywhere in the world in 8 hours (or less).
8 hours
8 hours
7 hours to Paris from Dulles, 8 hours to London or Rome
About 8 hours
about 8 hours and abit
About 7-8 hours.
It takes about 7-8 hours.
It takes around 8 Hours!
It takes about 8 1/2 hours.
8 hours
8 hours
6-8