Task: Question Answering
Input (English): Problem: calculate how long it will take a swimmer to swim a distance of 10 km against the current of a river which flows at 3 km / hr , given that he can swim in still water at 5 km / h 
Options: a ) 3 , b ) 4 , c ) 5 , d ) 6 , e ) 7
Output (English): c