A binary liquid mixture of A $($more volatile component$)$ and B $($less volatile component$)$ is to be continuously

distilled in a plate column. Components A and B form an ideal mixture over the entire composition range.

The relative volatility is constant and equals $2\mathrm{.}8.$ The column design and operating conditions are:

Determine: $($a$)$ the minimum number of theoretical plates; $($b$)$ the minimum reflux ratio; and $($c$)$ the number

of ideal stages required if the column is operated at a reflux ratio of $1\mathrm{.}5$ times the minimum.