Task: Question Answering
Input (English): Problem: machine a can finish a job in 6 hours , machine в can finish the job in 12 hours , and machine с can finish the job in 8 hours . how many hours will it take for a , b , and с together to finish the job ? 
Options: a ) 6 / 5 , b ) 7 / 4 , c ) 8 / 3 , d ) 9 / 2 , e ) 12 / 5
Output (English): c