Task: Question Answering
Input (English): Problem: a boatman goes 4 km against the current of the stream in 4 hour and goes 1 km along the current in 20 minutes . how long will it take to go 6 km in stationary water ? 
Options: a ) 5 hours , b ) 1 hours , c ) 3 hours , d ) 2 hours , e ) 4 hours
Output (English): c