Task: Question Answering
Input (English): Problem: two pipes a and b can separately fill a tank in 16 and 18 minutes respectively. a third pipe c can drain off 45 liters of water per minute. if all the pipes are opened, the tank can be filled in 18 minutes. what is the capacity of the tank ?
Options: a. 590 liters, b. 720 liters, c. 740 liters, d. 860 liters, e. 620 liters
Output (English): b