Subject: mathqa
Question: a boatman goes 2 km against the current of the stream in 1 hour and goes 1 km along the current in 15 minutes . how long will it take to go 5 km in stationary water ?
Option: 
A: 1 hour 40 min
B: 40 minutes
C: 1 hour 30 min
D: 1 hour
Answer: A