Answer the question

Tobias rode his bike on a road for a 2 hr period. On average, he passed a 1 km marker every 3 min during this period. Which of the following was his average speed for this 2 hr period?
Select from:
1). 10 km/hr
2). 15 km/hr
3). 20 km/hr
4). 25 km/hr
3).