Question 1
A car and a bus left City A at the same time and traveled along the same road to City B which was 160 km away. They ran at different but constant speeds which were integral numbers of km per hour. The difference in their speeds was a prime number of km per hour. After traveling for two hours, the distance the car had covered was five times the distance the bus still had to cover. What is the speed, in km per hour, of the bus?