A can do a piece of work in 2 hours; B and C together can do it in 3 hours, while A and C together can do it in 2 hours. How long will B alone take to do it?  Pick
A) 12
B) 9
C) 8
D) 6
E) 3
A's 1 hour's work = 1/2 ;   (B + C)'s 1 hour's work = 1/3 ;   (A + C)'s 1 hour's work = 1/2 .   (A + B + C)'s 1 hour's work = ( 1/2 + 1/3 ) =5/6 .   B's 1 hour's work = ( 5/6 - 1/2 ) = 1/3.   Therefore A alone will take 3 hours to do the work.   3
<result>E</result>
A can do a piece of work in 2 hours; B and C together can do it in 3 hours, while A and C together can do it in 2 hours. How long will B alone take to do it?