The Benzene$-$Toluene mixture containing $42\%($mole$)$ Benzene will be separated in a multi$-$tray$/$rack separator. Some part

This distillation column with condenser and a boiler contains $70\%($mole$)$ Benzene and $10\%$ in the other part.

$($mole$)$ It is used to separate the mixture into benzene.

a$)$ How many actual $($physical$)$ trays$/$shelves are needed in the column.

b$)$ When the feed is given to the column as $75\%$ saturated vapor and $25\%$ saturated liquid, the reflux ratio is $1\mathrm{.}5$ and

How many actual $($physical$)$ trays$/$racks are needed when the overall tray$/$rack efficiency is $40\%?$

e$)$ What is the minimum flow rate?

For calculations, you can take the relative volatility as $2\mathrm{.}5.$