Task: Question Answering
Input (English): Question: Two pipes A and B can separately fill a cistern in 80 minutes and 160 minutes respectively. There is a third pipe in the bottom of the cistern to empty it. If all the three pipes are simultaneously opened, then the cistern is full in 40 minutes. In how much time, the third pipe alone can empty the cistern?

 Option A: 90 min

 Option B: 160 min

 Option C: 110 min

 Option D: 120 min

 Option E: 130 min
Output (English): Option B