Time = (distance) / (speed) = (4,700 km) / (790 km/hr) = 5.95 hours
Velocity =
(distance from the start-point to the end-point)
divided by
(time for the trip) .
If the airplane went 4,700 km away, then turned around and returned
to its starting point, then the distance from the start-point to the end-point
is zero, and the average velocity for the trip is zero.