A pump can fill a tank with water in 3 hours. Because of a leak, it took 3 1/3 hours to fill the tank. The leak can drain all the water of the tank in?	Choose the correct choice from the following choices:
A) 17 hr	B) 19 hr	C) 30 hr	D) 14 hr	E) 16 hr

Rationale: "work done by the tank in 1 hour = ( 1 / 3 - 3 1 / 3 ) = 1 / 30 leak will empty the tank in 30 hrs . answer : c"
Answer: C