In a screen separator, the mass flow rates of feed, overflow and underflow are 150,140 and $10 \mathrm{~kg} \mathrm{~h}^{-1}$, respectively. Mass fraction of material in the feed and overflow are 0.9 and 0.96 , respectively. The effectiveness of separation in percentage is
(A) 32
(B) 42
(C) 52
(D) 62
In a screen separator, the mass flow rates of feed, overflow and underflow are 150,140 and $10 \mathrm{~kg} \mathrm{~h}^{-1}$, respectively. Mass fraction of material in the feed and overflow are 0.9 and 0.96 , respectively. The effectiveness of separation in percentage is
(A) 32
(B) 42
(C) 52
(D) 62