An air stream at $250$C at a pressure of $1$ atmosphere pressure is to be controlled by an activated carbon bed.

Determine the adsorption capacity of the carbon for the following concentrations of benzene

$1.800$ ppm

$2.1500$ ppm

$3.3000$ ppm

The coefficients a$,$ b and d for benzene are $-1\mathrm{.}189,0\mathrm{.}288$ and $-0\mathrm{.}0238$ respectively.