Design a carbon absorption system for a dilute stream of hexane in a $5500$ acfm air flow. You will need $110$ ft$^3$of carbon $(4\backslash$times $6$ mesh$),$ and the minimum bed depth should be $1$ ft$.$ Calculate the pressure drop in the bed for depths of $1\mathrm{.}0,1\mathrm{.}5,$ and $2\mathrm{.}0$ ft$.$