please draw the graph of Langmuir isotherm. How to calculate the qmax$=269\mathrm{.}78$ and Kl$=0\mathrm{.}395$ L$/$mg$?$ how to calculate the minimum dose of activated carbon for needed for reducing toluen from $20$mg$/$L to $0\mathrm{.}1$ mg$/$L$?$ please explain the way you calculate into $0\mathrm{.}087$ g$/$L