Task: Question Answering
Input (English): Problem: it was calculated that 75 men could complete a piece of work in 20 days . when work was scheduled to commence , it was found necessary to send 25 men to another project . how much longer will it take to complete the work ? 
Options: a ) 10 , b ) 30 , c ) 20 , d ) 15 , e ) 40
Output (English): b