A distillation column separates 10,000 kg/h of a 50 wt% benzene-50% toluene mixture. The top product contains 95% benzene and the bottom product (B) contains 96% toluene. 7000 kg/h of vapour (V) from...

A distillation column separates 10,000 kg/h of a 50 wt% benzene-50% toluene mixture. The top product contains 95% benzene and the bottom product (B) contains 96% toluene. 7000 kg/h of vapour (V) from the top of the column enters the condenser where it is totally condensed to liquid. A portion of this liquid is returned to the distillation column as reflux (R) and the remainder is withdrawn as top product (D).
a) Determine the bottom stream flowrate
b) Find the composition of vapour stream