In this task, you need to answer the given multiple-choice question on the physics. Classify your answers into 'a', 'b', 'c', 'd', and 'e'.

Problem: a cistern which could be filled in 10 hours takes 2 hour more to be filled owing to a leak in its bottom . if the cistern is full , in what time will the leak empty it ?
Options: a ) 50 hours , b ) 80 hours , c ) 100 hours , d ) 150 hours , e ) 110 hours
e