Adistillation column separates 16,000 kg/h of a 70% benzene and 30% toluene. the product recovered from the top contains 95% benzene while the bottom product contains 96% toluene. the stream entering the condenser from the top of the column is 8,000 kg/h. a portion of the product is returned to the column as reflux and the remaining is withdrawn as top product. find the ratio of the amount refluxed to the product taken out.