1 km = 1000 meters.
Find total meters: 80 km x 1000 meters per km = 80,000 meters.
Divide total meters by the given speed:
80,000 meters / 180 m/s = 444.44 seconds.
1 minute = 60 seconds
444.44. Seconds / 60 seconds per minute = 7.41 minutes = 7 minutes 24.42 seconds
Total time = 7 minutes 24.42 seconds
Round as needed.