Pipes A and B can fill a tank in 8 hours and 12 hours, respectively. C is an outlet pipe. When all the three are opened together, the tank is filled in \(13\frac{1}{3}\) hours. C alone can empty the full tank in:
1
\(6\frac{1}{2}\) hours
2
\(7\frac{1}{2}\) hours
3
8 hours
4
6 hours