A pipe can fill a tank in 16 minutes and a second one fill it in 24 minutes. A third pipe can empty that full tank in 8 minutes. The first two pipes are kept open for 4 minutes in the beginning and then the third pipe is opened. Then the time in which the tank will be. emptied after all the three pipe started working simultaneously (in minutes)?

A

20

B

24

C

28

D

32