2- Copper sulfate in a processed ore containing inert solid and copper sulfate is extracted with pure water in a countercurrent multistage extraction system. The ore to be extracted contains 9000kg/h inert solid (B), 1000kg/h copper sulfate (A) and 400kg/h5u(C). It is desired to recover 951% of the copper sulfate in the ore. Exit -The washing solution contains 90% water and 10% copper sulfate. The downstream N0.5kg inert solid/kg aqueous solution is kept constant. Find the liquid flow rate in the downstream after liquefaction. a) 18000kg/hr b) 19000kg/hr c) 17000kg/hr d) 16000kg/hr