The speed of Ashu is 15 km/h more than the speed of Vishnu. They start moving in the same direction at the same time, but initially Vishu is ahead of Ashu by a certain distance. If Ashu crosses Vishu 6 hours after they start moving, what is the initial distance between them?
1
45 km
2
60 km
3
90 km
4
80 km