Task: Question Answering
Input (English): Problem: a contractor undertakes to built a walls in 50 days . he employs 70 peoples for the same . however after 25 days he finds that only 40 % of the work is complete . how many more man need to be employed to complete the work in time ? 
Options: a ) 105 , b ) 30 , c ) 35 , d ) 20 , e ) none of these
Output (English): a