A policeman chases after a thief who has a 400 KM head start. They run at constant speeds, with the policeman running 10 km every 6 minutes and the thief 10 km every 10 minutes. How long will policeman take to catch up with the thief?
A) 3 hrs
B) 5 hrs
C) 8 hrs
D) 10 hrs
E) 15 hrs
