Task: Question Answering
Input (English): Problem: if 20 men can build a water fountain 56 metres long in 14 days , what length of a similar water fountain can be built by 35 men in 3 days ? 
Options: a ) 21 m , b ) 24 m , c ) 27 m , d ) 29 m , e ) 30 m
Output (English): a